diff --git a/functions/src/models/consumption/electricity/consumption-electricity.ts b/functions/src/models/consumption/electricity/consumption-electricity.ts
index 638f815..b44ed3f 100644
--- a/functions/src/models/consumption/electricity/consumption-electricity.ts
+++ b/functions/src/models/consumption/electricity/consumption-electricity.ts
@@ -8,7 +8,7 @@ export interface ConsumptionElectricity {
   /**
    * The costs
    */
-  costs: number;
+  costs?: number;
   /**
    * The size of the household
    */
diff --git a/functions/src/models/consumption/heating/consumption-heating.ts b/functions/src/models/consumption/heating/consumption-heating.ts
index 11f9c3c..ef8309f 100644
--- a/functions/src/models/consumption/heating/consumption-heating.ts
+++ b/functions/src/models/consumption/heating/consumption-heating.ts
@@ -9,7 +9,7 @@ export interface ConsumptionHeating {
   /**
    * The costs
    */
-  costs: number;
+  costs?: number;
   /**
    * The size of the household
    */
diff --git a/functions/src/models/recurring-consumption/recurring-consumption-frequency-unit.ts b/functions/src/models/recurring-consumption/recurring-consumption-frequency-unit.ts
new file mode 100644
index 0000000..c247c80
--- /dev/null
+++ b/functions/src/models/recurring-consumption/recurring-consumption-frequency-unit.ts
@@ -0,0 +1,4 @@
+/**
+ * A recurring consumption frequency unit
+ */
+export type RecurringConsumptionFrequencyUnit = "daily" | "weekly" | "monthly";
diff --git a/functions/src/models/recurring-consumption/recurring-consumption-frequency.ts b/functions/src/models/recurring-consumption/recurring-consumption-frequency.ts
index 059ba29..dbc208d 100644
--- a/functions/src/models/recurring-consumption/recurring-consumption-frequency.ts
+++ b/functions/src/models/recurring-consumption/recurring-consumption-frequency.ts
@@ -1,3 +1,5 @@
+import { RecurringConsumptionFrequencyUnit } from "./recurring-consumption-frequency-unit";
+
 /**
  * A recurring consumption frequency
  */
@@ -5,7 +7,7 @@ export interface RecurringConsumptionFrequency {
   /**
    * The unit
    */
-  unit: "daily" | "weekly" | "monthly";
+  unit: RecurringConsumptionFrequencyUnit;
   /**
    * The weekdays.
    * Applicable if unit is set to `weekly`
diff --git a/functions/src/models/user/user.ts b/functions/src/models/user/user.ts
index 7c579db..88768b1 100644
--- a/functions/src/models/user/user.ts
+++ b/functions/src/models/user/user.ts
@@ -47,4 +47,12 @@ export interface User {
      * The city in country identifier
      */
     city?: string;
+    /**
+     * Whether marketing consent is provided
+     */
+    isMarketingConsentAllowed?: boolean;
+    /**
+     * The last accepted legal document version
+     */
+    acceptedLegalDocumentVersion?: number;
 }