There are tons of books and great podcasts on REI that will put you ahead of the game and you will add great value to your mentor. 

If you can leverage other people's money and come out ahead, that's the way you grow and expand.

@Issac Bacilio,Scroll down to the bottom of the page and click on "FilePlace". 

I'm in the exact same boat as you are @Thomas Mackay. 21 and looking to start house hacking.While not from my own experience, I've seen on other threads where people strongly recommend not getting too ahead of yourself.

I am not saying the world is going to end, but I do think a very rough period is up ahead.

I'm more than happy to move ahead at the agreed-upon terms.  

You would have been able to have a definite answer on the tax impact of your home sale ahead of time instead of changing numbers and software and being surprised by results. 

If you already own a home you're WAY ahead of your peers, and you'll be set up for a lifetime of successful REI if you keep learning and working hard.

@Nijha London - starting with a lending is the right way to go, you're already ahead of the curve.

Until you're experienced or decide on a very specific niche, I wouldn't recommend planning ahead for an as yet undiscovered seller financing deal.