The last time it was for one of my other business (computer software) - I partnered with a local college and helped some of their students get to a conference related to their subject, it made for a nice 'community conscious' angle, and got picked up by some local papers.

I remember one rent house I was a partner in, and the tenants were using one of the bedrooms as a "trash and dirty diaper room".

We were to be partners in converting these apartments into condos to sell.

And last, I need someone to be accountable too (besides my partner).

The big things are being able to have individual project areas with distince financial info, but also have an umbrella ability to see how they are all doing, with information about each partners investment across all projects or a single project.

My partner and I are in the process of addressing ways to get around the fear of investing in a buyer's market.

I have a potential partner who is willing to go in with me on a cash purchase.

My goal here at biggerpockets is to learn ways in finding great deals and partnering with investors in completing those deals.

How early on would you write a contract between you and your business partner?

My partners and I do it every year whether we need to or not.So I would add to your post... not only when starting out, but every year thereafter.