Lender wants appraisal of rents...on a rented house

[Bonnie Low]

Well, this is a new one for us. We're in the process of a BRRRR. We're doing a cash out refi from our hard money loan into a conventional 30 yr fixed. The property has been rented since December of 2020 and we have the tenant in there with a 1 year lease. It is managed by a professional property management company in our area. The house itself was already appraised for about what we expected it to. But now the lender is requiring a "rent appraisal" evidently to determine how much it should rent for. Why would they require this when we can show them a 1 yr lease and receipts for what it is actually renting for?? We're confident it's in line with the market so I'm more annoyed than concerned, but it feels like just yet another delay tactic and hurdle. Can any lenders out there explain what this is about?