New to BP, Looking to expand rental property portfolio

[Jimmy Jefferson]

Hi all, I'm new to BP, and currently have 2 rentals in my local area (Doylestown / Sellersville / Perkasie / Quakertown , Pennsylvania).  These towns are about 1 hour north of Philadelphia and 35 minutes south of the Lehigh Valley (Bethlehem / Allentown).  I'm looking to make any connections while also growing my real estate portfolio.  Couple quick questions...

1) Anyone in this general area... what are some of the best strategies for building your portfolio with limited capital? Success with BRRRR, seller financing, etc? I just used up a good chunk of my equity for my last rental purchase. I do not want to wait until I save up another $50K to buy another property.

2) Besides rentometer.com what other sources have people used to collect reliable rental income data?

Thanks,

Jimmy