diff --git a/BankingClientModel/src/commonMain/kotlin/net/codinux/banking/client/model/BankAccount.kt b/BankingClientModel/src/commonMain/kotlin/net/codinux/banking/client/model/BankAccount.kt
index 53a90768..32afd735 100644
--- a/BankingClientModel/src/commonMain/kotlin/net/codinux/banking/client/model/BankAccount.kt
+++ b/BankingClientModel/src/commonMain/kotlin/net/codinux/banking/client/model/BankAccount.kt
@@ -25,8 +25,8 @@ open class BankAccount(
     var haveAllTransactionsBeenRetrieved: Boolean = false,
     val countDaysForWhichTransactionsAreKept: Int? = null,
 
-    val bookedTransactions: MutableList<AccountTransaction> = mutableListOf(),
-    val unbookedTransactions: MutableList<UnbookedAccountTransaction> = mutableListOf(),
+    open val bookedTransactions: MutableList<AccountTransaction> = mutableListOf(),
+    open val unbookedTransactions: MutableList<UnbookedAccountTransaction> = mutableListOf(),
 
     var userSetDisplayName: String? = null,
     var displayIndex: Int = 0,
diff --git a/BankingClientModel/src/commonMain/kotlin/net/codinux/banking/client/model/CustomerAccount.kt b/BankingClientModel/src/commonMain/kotlin/net/codinux/banking/client/model/CustomerAccount.kt
index 2c4fa674..5a3a915a 100644
--- a/BankingClientModel/src/commonMain/kotlin/net/codinux/banking/client/model/CustomerAccount.kt
+++ b/BankingClientModel/src/commonMain/kotlin/net/codinux/banking/client/model/CustomerAccount.kt
@@ -7,7 +7,7 @@ import net.codinux.banking.client.model.tan.TanMethod
 
 @Suppress("RUNTIME_ANNOTATION_NOT_SUPPORTED")
 @NoArgConstructor
-open class CustomerAccount(
+open class CustomerAccount( // TODO: is actually a UserAccount
     val bankCode: String,
     var loginName: String,
     /**
@@ -21,7 +21,7 @@ open class CustomerAccount(
     val customerName: String,
     val userId: String = loginName,
 
-    val accounts: List<BankAccount> = emptyList(),
+    open val accounts: List<BankAccount> = emptyList(),
 
     /**
      * Identifier of selected TanMethod.
@@ -30,7 +30,7 @@ open class CustomerAccount(
      * [selectedTanMethod] to get selected TanMethod or iterate over [tanMethods] and filter selected one by this id.
      */
     val selectedTanMethodId: String? = null,
-    val tanMethods: List<TanMethod> = listOf(),
+    open val tanMethods: List<TanMethod> = listOf(),
 
     /**
      * Identifier of selected TanMedium.
@@ -39,7 +39,7 @@ open class CustomerAccount(
      * to get selected TanMedium or iterate over [tanMedia] and filter selected one by this medium name.
      */
     val selectedTanMediumName: String? = null,
-    val tanMedia: List<TanMedium> = listOf(),
+    open val tanMedia: List<TanMedium> = listOf(),
 
     var bankingGroup: BankingGroup? = null,
     var iconUrl: String? = null,