I have a great credit score but no money right now because it’s hard to get a job with a felony.

So that’s the background and my question is how does a young person with not much credit history get a loan for something like that?

Credit Risk.

How is their credit?

One more thing, I am not sure if you are using the lender you're using because you have a previous relationship with them, but with my lender the down payment for an investment can be as low as 15% (and I don't have any other investment properties under my belt or stellar credit).

Two lenders I have used in the past have told me that you need a credit score of at least 720 due to fannie mae regulations to refinance properties 7-10. 

I know she has iffy credit so have started thinking about lease to own for tenant.

The problem is you'll get someone that reads an advertisement and does not come anywhere close to qualifying, but then wants to say it was too good to be true.I get people all the time that have low credit scores,  can't prove their income and want 100% financing.Best thing to do is fill out a complete application and allow your credit to be pulled and do it the right way

Its like a big credit card.

If you have fair credit, verifiable rental history and consistent income you can easily secure FHA financing in Houston and the inner city is the ideal place to house hack because of it's proximity to all the cool and trendy places downtown along with the major universities and Med Center.