It's going to depend on the lender, how it's titled and what kind of refinance you are doing.If you're doing a conventional cash out refinance, a lot of lenders are going to require a 3 to 6 month seasoning period prior to refinancing and it will have to be rented first.

8 in 24 months is no joke, especially chipping away one at a time, I'm sure it has come with plenty of teachable moments, but its awesome that you are able to ask the question of how to scale.To start, a hard money lender that is only allowing you to do one at a time with your track record is... well... kind of silly.

For example, we do background checks but no proof of income/employment check.

In addition to checking into a conventional loan you can look into creative financing.

Thats that nature of any kind of leverage - it cuts both ways. 

@Angel Perez  You should also check out smaller local banks and ask to speak to the commercial lending department. 

Bigger Pockets is a great place for education and networking and is full of great content.I recommend that you check out the following resources:1.

What kind of documentation I need to get so I don't lose my capital.A neighbor of mine came with this ask of funding for building houses .

Then, if your a member of NAR, you better check on that and make sure your not making conflicts there. 

As boring as accounting sounds, I think it's a great degree so check that out if you want to go that route.