I'm a mortgage broker in Utah and I do a lot of DSCR. Figured I'd write up the things I watch blow up files, since most of them are avoidable if you know about them going in.

Rent documentation mismatches. Lenders pull rent two ways: the appraiser's 1007 market rent schedule, and your actual lease. Some programs take the lower of the two. If your lease is below market because you gave a tenant a deal, that's the number they use. If you're counting on a lease, have two months of proof that rent was actually received. A signed lease with no bank deposits behind it doesn't count.

Vacant on a refinance. If the property is empty when you refi, most lenders cut max LTV by about 10%. Get it leased first if you can.

Listed for sale in the last six months. A lot of programs won't touch a property that was recently on the market. If you listed it, pulled it, and now want to refi, expect a wait.

Short-term rental income. Not treated the same as long-term. Some lenders won't count it at all. Others will but reduce your max LTV or require documented operating history. Don't assume your Airbnb projections qualify you.

Small loan amounts need a higher ratio. On loans under $150,000, a lot of programs jump the minimum DSCR from 1.0 to 1.25. That catches people buying cheap doors, which is exactly the strategy where it hurts most.

Declining market designation. If the appraiser flags the market as declining, you can lose LTV or face a higher minimum ratio. You won't know until the appraisal comes back.

Property type. Condos with high investor concentration, manufactured homes, and co-ops are where files die. Rural can also reduce max LTV depending on the lender.

The thing nobody tells you: guidelines vary enormously between lenders. One will require 1.0 minimum, another has no minimum at all. One requires six months of reserves, another requires none under a certain loan amount. Same borrower, same property, different answer. If you got declined, it's worth asking whether it was the deal or the lender.

Happy to answer questions on specifics. Guidelines change constantly, so treat anything above as a snapshot.