DTI - 10% Down Payment Strategy

[Brian Wilson]

My understanding is that when purchasing a STR property using a 10% second home loan, you can't use potential STR revenue to qualify for the loan.

If this understanding is true, does your revenue count towards reducing DTI when you are pursuing additional 10% second home loans in different markets?

Second question, what qualifies as a different market? Is it a certain mileage separation (over 50 miles)? Or state based. 

Thanks everyone!