diff --git a/app/src/frontend/building/data-components/numeric-data-entry.tsx b/app/src/frontend/building/data-components/numeric-data-entry.tsx
index 9fbf8cc7..15c0c740 100644
--- a/app/src/frontend/building/data-components/numeric-data-entry.tsx
+++ b/app/src/frontend/building/data-components/numeric-data-entry.tsx
@@ -27,10 +27,10 @@ const NumericDataEntry: React.FunctionComponent<NumericDataEntryProps> = (props)
                 type="number"
                 id={props.slug}
                 name={props.slug}
-                value={props.value || ''}
-                step={props.step || 1}
+                value={props.value == undefined ? '' : props.value}
+                step={props.step == undefined ? 1 : props.step}
                 max={props.max}
-                min={props.min || 0}
+                min={props.min}
                 disabled={props.mode === 'view' || props.disabled}
                 placeholder={props.placeholder}
                 onChange={e => 
diff --git a/app/src/frontend/building/data-components/year-data-entry.tsx b/app/src/frontend/building/data-components/year-data-entry.tsx
index 1d35f8ee..3a9c2996 100644
--- a/app/src/frontend/building/data-components/year-data-entry.tsx
+++ b/app/src/frontend/building/data-components/year-data-entry.tsx
@@ -30,6 +30,8 @@ class YearDataEntry extends Component<YearDataEntryProps, any> {
     // TODO handle changes internally, reporting out date_year, date_upper, date_lower
     render() {
         const props = this.props;
+
+        const currentYear = new Date().getFullYear();
         return (
             <Fragment>
                 <NumericDataEntry
@@ -39,6 +41,8 @@ class YearDataEntry extends Component<YearDataEntryProps, any> {
                     mode={props.mode}
                     copy={props.copy}
                     onChange={props.onChange}
+                    min={1}
+                    max={currentYear}
                     // "type": "year_estimator"
                     />
                 <NumericDataEntry
@@ -49,6 +53,8 @@ class YearDataEntry extends Component<YearDataEntryProps, any> {
                     copy={props.copy}
                     onChange={props.onChange}
                     step={1}
+                    min={1}
+                    max={currentYear}
                     tooltip={dataFields.date_upper.tooltip}
                     />
                 <NumericDataEntry
@@ -59,6 +65,8 @@ class YearDataEntry extends Component<YearDataEntryProps, any> {
                     copy={props.copy}
                     onChange={props.onChange}
                     step={1}
+                    min={1}
+                    max={currentYear}
                     tooltip={dataFields.date_lower.tooltip}
                     />
             </Fragment>
diff --git a/app/src/frontend/building/data-containers/age.tsx b/app/src/frontend/building/data-containers/age.tsx
index 1f1728b6..0e886d16 100644
--- a/app/src/frontend/building/data-containers/age.tsx
+++ b/app/src/frontend/building/data-containers/age.tsx
@@ -13,69 +13,75 @@ import { CategoryViewProps } from './category-view-props';
 /**
 * Age view/edit section
 */
-const AgeView: React.FunctionComponent<CategoryViewProps> = (props) => (
-    <Fragment>
-        <YearDataEntry
-            year={props.building.date_year}
-            upper={props.building.date_upper}
-            lower={props.building.date_lower}
-            mode={props.mode}
-            copy={props.copy}
-            onChange={props.onChange}
-            />
-        <NumericDataEntry
-            title={dataFields.facade_year.title}
-            slug="facade_year"
-            value={props.building.facade_year}
-            mode={props.mode}
-            copy={props.copy}
-            onChange={props.onChange}
-            step={1}
-            tooltip={dataFields.facade_year.tooltip}
-            />
-        <SelectDataEntry
-            title={dataFields.date_source.title}
-            slug="date_source"
-            value={props.building.date_source}
-            mode={props.mode}
-            copy={props.copy}
-            onChange={props.onChange}
-            tooltip={dataFields.date_source.tooltip}
-            placeholder=""
-            options={[
-                "Survey of London",
-                "Pevsner Guides",
-                "Local history publication",
-                "National Heritage List for England",
-                "Historical map",
-                "Archive research",
-                "Expert knowledge of building",
-                "Other book",
-                "Other website",
-                "Other"
-            ]}
-            />
-        <TextboxDataEntry
-            title={dataFields.date_source_detail.title}
-            slug="date_source_detail"
-            value={props.building.date_source_detail}
-            mode={props.mode}
-            copy={props.copy}
-            onChange={props.onChange}
-            tooltip={dataFields.date_source_detail.tooltip}
-            />
-        <MultiDataEntry
-            title={dataFields.date_link.title}
-            slug="date_link"
-            value={props.building.date_link}
-            mode={props.mode}
-            copy={props.copy}
-            onChange={props.onChange}
-            tooltip={dataFields.date_link.tooltip}
-            placeholder="https://..."
-            />
-    </Fragment>
-);
+const AgeView: React.FunctionComponent<CategoryViewProps> = (props) => {
+    const currentYear = new Date().getFullYear();
+    
+    return (
+        <Fragment>
+            <YearDataEntry
+                year={props.building.date_year}
+                upper={props.building.date_upper}
+                lower={props.building.date_lower}
+                mode={props.mode}
+                copy={props.copy}
+                onChange={props.onChange}
+                />
+            <NumericDataEntry
+                title={dataFields.facade_year.title}
+                slug="facade_year"
+                value={props.building.facade_year}
+                mode={props.mode}
+                copy={props.copy}
+                onChange={props.onChange}
+                step={1}
+                min={1}
+                max={currentYear}
+                tooltip={dataFields.facade_year.tooltip}
+                />
+            <SelectDataEntry
+                title={dataFields.date_source.title}
+                slug="date_source"
+                value={props.building.date_source}
+                mode={props.mode}
+                copy={props.copy}
+                onChange={props.onChange}
+                tooltip={dataFields.date_source.tooltip}
+                placeholder=""
+                options={[
+                    "Survey of London",
+                    "Pevsner Guides",
+                    "Local history publication",
+                    "National Heritage List for England",
+                    "Historical map",
+                    "Archive research",
+                    "Expert knowledge of building",
+                    "Other book",
+                    "Other website",
+                    "Other"
+                ]}
+                />
+            <TextboxDataEntry
+                title={dataFields.date_source_detail.title}
+                slug="date_source_detail"
+                value={props.building.date_source_detail}
+                mode={props.mode}
+                copy={props.copy}
+                onChange={props.onChange}
+                tooltip={dataFields.date_source_detail.tooltip}
+                />
+            <MultiDataEntry
+                title={dataFields.date_link.title}
+                slug="date_link"
+                value={props.building.date_link}
+                mode={props.mode}
+                copy={props.copy}
+                onChange={props.onChange}
+                tooltip={dataFields.date_link.tooltip}
+                placeholder="https://..."
+                />
+        </Fragment>
+    );
+};
 const AgeContainer = withCopyEdit(AgeView);
 
 export default AgeContainer;
diff --git a/app/src/frontend/building/data-containers/location.tsx b/app/src/frontend/building/data-containers/location.tsx
index 5e437b1f..8d82445e 100644
--- a/app/src/frontend/building/data-containers/location.tsx
+++ b/app/src/frontend/building/data-containers/location.tsx
@@ -31,6 +31,7 @@ const LocationView: React.FunctionComponent<CategoryViewProps> = (props) => (
             copy={props.copy}
             onChange={props.onChange}
             step={1}
+            min={1}
             />
         <DataEntry
             title={dataFields.location_street.title}
@@ -99,8 +100,10 @@ const LocationView: React.FunctionComponent<CategoryViewProps> = (props) => (
             value={props.building.location_latitude}
             mode={props.mode}
             copy={props.copy}
-            step={0.0001}
-            placeholder="51"
+            step={0.00001}
+            min={-90}
+            max={90}
+            placeholder="Latitude, e.g. 51.5467"
             onChange={props.onChange}
             />
         <NumericDataEntry
@@ -109,8 +112,10 @@ const LocationView: React.FunctionComponent<CategoryViewProps> = (props) => (
             value={props.building.location_longitude}
             mode={props.mode}
             copy={props.copy}
-            step={0.0001}
-            placeholder="0"
+            step={0.00001}
+            min={-180}
+            max={180}
+            placeholder="Longitude, e.g. -0.0586"
             onChange={props.onChange}
             />
     </Fragment>
diff --git a/app/src/frontend/building/data-containers/size.tsx b/app/src/frontend/building/data-containers/size.tsx
index 7ae4c2cf..114d2c5d 100644
--- a/app/src/frontend/building/data-containers/size.tsx
+++ b/app/src/frontend/building/data-containers/size.tsx
@@ -24,6 +24,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
                 tooltip={dataFields.size_storeys_core.tooltip}
                 onChange={props.onChange}
                 step={1}
+                min={0}
                 />
             <NumericDataEntry
                 title={dataFields.size_storeys_attic.title}
@@ -34,6 +35,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
                 tooltip={dataFields.size_storeys_attic.tooltip}
                 onChange={props.onChange}
                 step={1}
+                min={0}
                 />
             <NumericDataEntry
                 title={dataFields.size_storeys_basement.title}
@@ -44,6 +46,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
                 tooltip={dataFields.size_storeys_basement.tooltip}
                 onChange={props.onChange}
                 step={1}
+                min={0}
                 />
         </DataEntryGroup>
         <DataEntryGroup name="Height">
@@ -55,6 +58,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
                 copy={props.copy}
                 onChange={props.onChange}
                 step={0.1}
+                min={0}
                 />
             <NumericDataEntry
                 title={dataFields.size_height_eaves.title}
@@ -65,6 +69,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
                 copy={props.copy}
                 onChange={props.onChange}
                 step={0.1}
+                min={0}
                 />
         </DataEntryGroup>
         <DataEntryGroup name="Floor area">
@@ -76,6 +81,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
                 copy={props.copy}
                 onChange={props.onChange}
                 step={0.1}
+                min={0}
                 />
             <NumericDataEntry
                 title={dataFields.size_floor_area_total.title}
@@ -85,6 +91,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
                 copy={props.copy}
                 onChange={props.onChange}
                 step={0.1}
+                min={0}
                 />
         </DataEntryGroup>
         <NumericDataEntry
@@ -95,6 +102,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
             copy={props.copy}
             onChange={props.onChange}
             step={0.1}
+            min={0}
             />
         <NumericDataEntry
             title={dataFields.size_plot_area_total.title}
@@ -104,6 +112,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
             copy={props.copy}
             onChange={props.onChange}
             step={0.1}
+            min={0}
             disabled={true}
             />
         <NumericDataEntry
@@ -114,6 +123,7 @@ const SizeView: React.FunctionComponent<CategoryViewProps> = (props) => (
             copy={props.copy}
             onChange={props.onChange}
             step={0.1}
+            min={0}
             disabled={true}
             />
         <SelectDataEntry