I am 18 years old so I have absolutely no credit or money but I can get the downpayment from a private money source. 

Some found online and others through craigslist.

I have seen many online ads for mortgage lenders with seemingly better interest rates than I have found while inquiring around at local banks and credit unions.  

A good deal ought to give you some cash flow, and cover all your expenses for the property.In tandem with that, I'd go after as much education as possible online.

Quest is a company that you can google with a bunch of online answers.

There's some really cool people in this online community and they are just as cool in person too.

@Ian DavisRun the numbers with one of the many tools online, like Hector mentions - or even use the ones right on BP.

In the process of applying online, I was asked to obtain my credit report through a link they provided to a company called CreditNav. 

Online ones aren't too bad.

By the sounds of it the equity you have in your current properties is a significant tool you can use to secure financing of some kind including a home equity line of credit or maybe a refinance.