I've never used the rental version so I can't quite grasp the "attach" aspect of the question. I'd guess the rental version uses Tags to associate rental income to property and the Investment Accounts don't allow the use of Tags.One workaround - if I've guessed correctly - would be to set up a "dummy" bank Account, one not associated with any Financial Institution, and make your "deposits" there. That would allow the use of a Tag as part of the transaction. Then you zero out the dummy account with a Transfer to the brokerage Account where the deposit actually occurs. The transfer, of course, has no Tag that connects it to the rental unit.It's a little more work but the use of memorized transactions should reduce the effort somewhat.