I understand home designs are pretty expensive, and cannot just be applied to any lot/existing neighborhood.

The majority of states have NOT enacted any rules, regulations or legislation that has altered the “wholesaling” landscape.  

As @Chris Seveney mentioned there is not really enough equity in house 3 to get a meaningful LOC. even if you were able to leverage enough to pay off House 2 the new rate you would be paying would be higher than the existing mortgage, so you would still be behind overall.Your ROI on those payoffs vs keeping money in index funds is not very good either.Lastly, remember that cash flow from rentals can seem good until it’s not.

In my market zoning ordinances often make 95% of existing residential lots nonconforming where nothing could be built within the ordinance.

They lend you the money you need to buy their house.Subject to - you buy the house subject to the existing mortgage.

I was recently looking into wholesaling in PA around the Wilkes-Barre area and was wondering about the overall laws and regulations.

Maintain the seller’s existing insurance.2.

Additionally, the flexibility to use the units for housing existing commercial tenants during repairs added strategic value and aligned with my broader portfolio goals.

Your first post sounds like a purchase, but this statement "The $20,000 was when I refinanced and did HARP with Wells Fargo twice." makes it sound like a refi.If it was a refi, was this $20K an existing debt of yours that was not caught and paid off on the refi? 

Ensure it cash flows comfortably.Market & Location: Research local rental demand, property values, and any applicable LTR regulations to understand the area’s potential for long-term success.Future Potential: Consider if the property could appreciate or attract quality tenants over time, supporting stable cash flow and asset growth.This checklist should set you up for a solid LTR investment!