Purchasing subject to allows you to (1) buy a property and pay a lower rate (3-4%) that was in existence when the loan was originated, so cash flow will be better as well as equity buildup; (2) not have to qualify for the mortgage saving time, expense, and allowing property purchases in greater number than otherwise and (3) no personal liability on downside (4) no debt added to your PFS.  

You can still qualify so long as you have verifiable income.

Instead, keep the property in your name or transfer it to an LLC for liability protection.Since you’ve lived in the home for at least 2 of the last 5 years, selling now could qualify for a capital gains exclusion of up to $500K (MFJ) or $250K (single).

If they only make $2000 and know their income has to be $3000 or higher to qualify, they can apply elsewhere and save the $30 application fee.

An LLC is potentially one minor factor that might contribute to the evidence that you are running your rental activity as a trade or business, but it's definitely not required that you have an LLC to qualify.

Made sure to check the ledger and T12 to ensure that the tenant was qualified correctly before purchasing the property.

Several have mentioned utilizing low down payment second home loans for qualifying.

Sometimes, properties rented out for years as multifamily can qualify for a variance or grandfathering, depending on local laws. 

Any tips on finding qualified (key word) borrowers in my local area?

My suggestions would be in this order:(a) Determine the type of financing you qualify for - this will short cut the process considerably and save time on investment angles and next steps.