diff --git a/app/furniture/tobias/payment.rb b/app/furniture/tobias/payment.rb
index 34f5d7e2e..ddd1f0778 100644
--- a/app/furniture/tobias/payment.rb
+++ b/app/furniture/tobias/payment.rb
@@ -2,7 +2,7 @@ class Tobias
   class Payment < ApplicationRecord
     self.table_name = "tobias_payments"
 
-    belongs_to :payout
+    belongs_to :payout, inverse_of: :payments
 
     monetize :amount_cents
   end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 0cc9fbf52..7cd8f9340 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,6 +1,7 @@
 require "faker"
 require "pundit/rspec"
 require "simplecov"
+require "money-rails/test_helpers"
 
 SimpleCov.start do
   enable_coverage :branch
diff --git a/spec/tobias/payment_spec.rb b/spec/tobias/payment_spec.rb
new file mode 100644
index 000000000..19607f969
--- /dev/null
+++ b/spec/tobias/payment_spec.rb
@@ -0,0 +1,11 @@
+require "rails_helper"
+
+RSpec.describe Tobias::Payment, type: :model do
+  describe "#payout" do
+    it { is_expected.to belong_to(:payout).inverse_of(:payments) }
+  end
+
+  describe "#amount" do
+    it { is_expected.to monetize(:amount) }
+  end
+end