@Mya Toohey No lender, not even Non-QM lender, can interact with an appraiser and direct them to complete the appraisal a specific way. At the end of the day the Non-QM loans also do get aggregated to the same big money funds and then sold off into the secondary market, so they have to maintain the same standards.
Having said that, I have had success many time where the appraiser will complete the rent comp analysis using short term rental data. But this has mainly been in a heavy STR markets only. Think Smokey Mountains, Shenandoah Valley, etc. If the transaction is in a market with majority traditional transactions (OO or LTR), than you will have a very difficult time get the appraiser to complete the rent comp using STR data. The appraiser cares about their license and lively hood. They have to meet appraisal guidelines. I a market like Tampa/St Pete, I would always pre-approve based on LTR.
If the property is an existing STR and the seller will provide at least 12 months of history, than you have an entirely different transaction. Now you can do a full doc + 12 month "bank statement" income. This way even if the appraisal rental income is low, the DTI wouldn't be an issue. You can also employ the same process for refi. Hope this helps.
I have a 5% down 2nd home/Vacation home loan and 15% down investment loan that might add value to you and your clients. Would love to connect.