diff --git a/models/staging/core/_core_sources.yml b/models/staging/core/_core_sources.yml
index e4315ce..8f39616 100644
--- a/models/staging/core/_core_sources.yml
+++ b/models/staging/core/_core_sources.yml
@@ -5,7 +5,7 @@ sources:
     schema: sync_core
     tables:
       - name: User
-        description: A User. 
+        description: A User.
         columns:
           - name: Id
             data_type: character varying
@@ -40,48 +40,73 @@ sources:
             description: "The Hubspot Deal Id that this user account belongs to. Multiple users can all be part of one Deal."
             # This test can't be enforced yet due to some bad test data in the production database. Once that's deal with, this should be activated.
             #tests:
-              # - dbt_expectations.expect_column_values_to_match_regex:
-              #  regex: "^[0-9]{10,11}$"
+            # - dbt_expectations.expect_column_values_to_match_regex:
+            #  regex: "^[0-9]{10,11}$"
           - name: Deleted
             data_type: boolean
             quote: True
             description: "WIP. I'm guessing this signals that the user wanted to be deleted?"
-          - name: joindate
+            tests:
+              - not_null
+          - name: JoinDate
             data_type: timestamp without time zone
-            description: ""
-          - name: lastname
+            quote: True
+            description: "Timestamp on which the user was created."
+            tests:
+              - not_null
+          - name: LastName
             data_type: character varying
+            quote: True
             description: ""
-          - name: username
+          - name: UserName
             data_type: character varying
+            quote: True
             description: ""
-          - name: firstname
+            tests:
+              - not_null
+          - name: FirstName
             data_type: character varying
+            quote: True
             description: ""
-          - name: codeprefix
+          - name: CodePrefix
             data_type: character varying
-            description: ""
-          - name: billingtown
+            quote: True
+            description: "WIP. No clue on what is this."
+          - name: BillingTown
             data_type: character varying
+            quote: True
             description: ""
-          - name: companyname
+          - name: CompanyName
             data_type: character varying
+            quote: True
             description: ""
-          - name: dateofbirth
+          - name: DateOfBirth
             data_type: timestamp without time zone
+            quote: True
             description: ""
-          - name: phonenumber
+          - name: PhoneNumber
             data_type: character varying
+            quote: True
             description: ""
-          - name: passwordhash
+          - name: PasswordHash
             data_type: character varying
+            quote: True
             description: ""
-          - name: accounttypeid
+          - name: AccountTypeId
             data_type: bigint
+            quote: True
             description: ""
-          - name: createduserid
+          - name: CreatedUserId
             data_type: character varying
-            description: ""
+            quote: True
+            description: | 
+              A user can be created by another user. If this user has been created by another user, this is the UUID of the creator. 
+              
+              Else, this is null.
+            tests:
+              - dbt_expectations.expect_column_values_to_match_regex:
+                  regex: "^[0-9A-Fa-f]{8}-[0-9A-Fa-f]{4}-4[0-9A-Fa-f]{3}-[89ABab][0-9A-Fa-f]{3}-[0-9A-Fa-f]{12}$"
+                  row_condition: '"CreatedUserId" is not null'
           - name: securitystamp
             data_type: character varying
             description: ""