While your heart is in the right place, this sounds like the recipe for destruction of a friendship. 

Navigating house rules, rent payments, and other responsibilities while maintaining a friendship requires a delicate balance.

We ended up paying him close to 1/3 to make a clean cut, but our friendship basically dissolved in the process, despite everyone coming out on top. 

The first time I started a business with a friend I told him, "your friendship is more important to me than any business".

One ended in a court case and the end of a friendship that caused others to take sides and destroyed several other friendships as well it also ended with a business going bankrupt and costing $200,000 for the “winning” partner which was me.

I hope this doesn't ruin our friendship and I attend not to let that happen, but I also don't want to own a property that will ruin myself or my marriage with my wife.

Take the friendship out of the equation and treat it as a business venture. 

I don't do christmas presents for tenants, I guess I feel like it blurrs the friendship/customer relationship line.

During college everyone is around you and near you, primed to create friendships vs post-college where people get stuck in their mundane routine and as a result a pattern of isolation.

The community itself is great, I made many new friendships and keep learning all the time.