you can just simulate a 15 year by making larger payments if you want 

Run different simulations with realistic expectations to determine what makes sense for you.

It even does Monte Carlo simulations (bonus points to anyone that knows that - beer on me when you're in Denver!)

(Theoretically)It ain’t gonna happen anytime soon or probably not even in my life time.But I’m sure you run an excel program and run the simulation it’ll show you that there is the possibility of it not happening.

When you are ready to move out, then execute the house hacking strategy.Another way to simulation ownership is to pick a property, run the numbers, then "pay" yourself the mortgage payment (PITI) - reduced by realistic rent income, estimated utilities, CapEx, vacancy. 

You need to have a plan and do cost simulation and work with the same lender that will benefit you.

Here's another angle :- If interest rate is cheap enough, you don't really have to add more into principal but if rate is above 5%, then it's a good practice- HOWEVER, paying principle down is useful especially IF you want to hold property for certain number of years and plan to sell it (in your case 10 years) ; AND also IF acceleration of the appreciation equity of that place is twice than mortgage rate (eg: if appreciation per monthly is 5k/month and mortgage is 2k, then paying off asset early is GOOD).What I am saying is this:- if your rate is 2% and your location is in Cupertino,CA then definitely adding principal is good- if your rate is 6% and your location is in Cupertino,CA then definitely adding principal is a MUST- if your rate is 5% and your location is in detroit michigan then forget about adding principalit really depends on the market, you can simulate this in excel using amortization calculator to understand what I meant.This is my basis strategy how to payoff 30YFRM in 10-12 years only.

But Chris is correct that the solar companies can run a simulator to get an pretty accurate idea of your production.

For example, 25 years ago, I simulated the long-term impact of investing an additional $100 a month (or whatever).

I started doing some sample simulations of potential properties to get a better understanding of how to analyze a profitable investment and of course doing this as an exercise helps with the learning curve.