Is it appropriate to ask if someone is willing to pass on a purchase & sale agreement template they use?

I want to make the best decision while honoring my agreements and maintaining professional integrity in this deal.

You would need an agreement in place for cost overruns.

That agreement will set a compensation that is negotiable.

Furthermore, there is likely an Affiliated Business Agreement Disclosure that you'll need to sign. 

So if the partnership would not be allowed to purchase the entity together and I were to buy it, if we were to force our way down this road, would be to set up a legal agreement beforehand, I would buy the property since a partnership can not, and then the exchange for  ($$ + assigned roles + etc), my partner receives 50% equity?  

Ensure your agreement with that person has teeth so if they sign off on something that isn't right they can be held liable for it. 

In the future, be very specific about these agreements.

You would work with other lenders and do a participation agreement, but many of them will require you to put in 20-40% of the money, have a net worth of 2x what they are including as they will want you to buy back the loan if it goes into default.3.

The Owners Agreement has been a big help as it delineates the exclusive use/rights and shared rights to each area of the property.