title: Error while writing Visualforce Controller Extension
body: <p>I am trying to write my first controller extension, and I am running into an error:</p>
  
  <p>Error: Compile Error: Initial term of field expression must be a concrete SObject: LIST at line 26 column 34    </p>
  
  <p>This is the code that generated the error:</p>
  
  <pre><code>public class CustFinAcctRelatedList{
  private households__Household__c RG;
  
  private List&lt;households__HouseholdMember__c&gt; RGMembs;
  private List&lt;Account&gt; Accts;
  private List&lt;Financial_Account__c&gt; finAccts;
  
  //Get Household Record from VisualForce Page//
  public CustFinAcctRelatedList(ApexPages.StandardController controller) {
      this.RG = (households__Household__c)controller.getRecord();
  }
  
  public List&lt;Financial_Account__c&gt; getFinAccts()
  {
      //Get Household Members (junction object between Account and Household) from Household//
      RGMembs = [
          SELECT id, households__Household__c, households__Account__c
          FROM households__HouseholdMember__c 
          WHERE households__HouseholdMember__c.households__Household__c = :RG.id
      ];
  
      //Get Accounts from Household Members (junction object between Account and Household)//
      Accts = [
          SELECT id
          FROM Account
          //****THE FOLLOWING LINE IS CAUSING THE ERROR****//
          WHERE Account.id IN :RGMembs.households__Account__c.id
      ];
  
      //Get Financial Account from Accounts//
      finAccts = [
          SELECT id, name, Client__r.name, Current_Value__c, Account_Type__c
          FROM Financial_Account__c
          WHERE Financial_Account__c.Client__c IN :Accts.id
      ];
  
      return finAccts;
  }
  }
  </code></pre>
  
  <p>Any idea why this error is being generated?</p>
  
  <p>I am going to use the return data to create a custom related list on a Visualforce page.</p>
  
  <p>Thanks!</p>