In both cases I spend a lot of money rehabbing a house and then pay myself back either through a sale or refinance of the property.Up to this point, I have primarily just paid for everything through my business checking account.

First off $20K should be enough money if your trying to get a construction loan done.

That being said being so quick to grab na property at my young age it may not have been the best deal; but I put 0 money down and actually got paid to purchase this property so I guess I didn't do too bad.

My goals with the money will be to retire early, travel (I am a Flight Attendant), pay off my parents mortgage, give back to those in need, save money, and be able to do the things I want to do without the burden of constantly worrying about money. 

Maybe use that money to invest in a couple rental homes first.

Here's some advice and insights on utilizing private money and home flipping to get started:Private Money: Lenders of funds to real estate investors that provide better returns on investment than standard financing choices are known as private money lenders.

We renovated property doing all the work ourselves so I'm not sure if we can factor in our labor into the money we put into the property, not just materials?

Don't forget, if you have owned a commercial property for a long time and have put a lot of money into it over the years, you may be able to expense many of those "improvements" with the Tangible Property Regulations (TPRs) of 2014.

The money making part though is the previous owners had built a detached studio that was mostly finished.

The risk here is what if I can't pull my money back out and don't get to cash out refi the amount I want.