You've done well with your Class A rental, generating $500/mo in cash flow, this adds up over time.

In my market using a HELOC on a rental doesn't even come close to working. 

I currently have a rental property and am looking at getting my real estate license and building a property management and property maintenance company to serve my investments and potentially others.  

@Jim LynchSome typical minimum tenant screening requirements look like the following, but it depends on your market:-Renter has a gross monthly income of 3x more than the monthly rent-Minimum credit score of 650-Renter must have no prior evictions-No felons (or other notable criminal history)There are a number of different tenant screening softwares out there such as Zillow Rental Manager, TransUnion SmartMove, etc.Be sure to complete an employment verification by contacting the renter's employer and confirm the details they shared with you, landlord verification (if they have a previous landlord), credit check, and background check.

AJ, is this a rental property that already have stabilized with a lease in place?

As always, DYOR (Do Your Own Research) The area has a mix of stable, long-term residents and rental demand—especially with Section 8 tenants—but it does vary block-by-block.Key things to consider are Rental Demand, Property Condition and Management (a local property manager can help navigate tenant screening and city requirements)It’s not as bad as the headlines make it seem, but success here depends on buying right and the right property manager.

I operate a few rentals in the Watertown NY area.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

In Pittsburgh it’s the only way to buy rentals haha!

Every investor has a different approach, but I personally buy my rentals the same way I buy my flips..at a deep discount using hard/private money, then refinance with a rate-and-term loan to secure a lowest interest rate.Ultimately, it comes down to your goals, risk tolerance, and ability to find value-add opportunities.