Rental Property Partnership Structure Questions

[Gordon A.]

I am considering partnering with a friend to purchase an investment property and I was wondering what the consensus was on a fair partnership structure. Here are the details:

1. The property is in his backyard (Boston). I live in LA so he will be doing much of the face to face leg work for purchasing, upkeep, and eventual tenant management.

2. I will pony up 85% a of the down payment, and he will contribute the remaining 15%.

3. He will live in the property for most likely 24 months while he pays the mortgage. If he cannot swing it, which is very possibly the most I will have to supplement would be 25% of that payment for up to the 24 months. 

4. A few months prior to the 24 months deadline, he will help coordinate and live in the property while it is remodeled a floor at a time. We will either pull the money out of the equity we have or pay cash 50/50 for the remodel.

5. Once remodeled he will move out and fill the property with tenants and assume ongoing management roles.

6. We plan to hold indefinitely, but there is always a chance we sell.

7. If repairs are needed they will be most likely funded by me due to his already strained financial position while living in the property.

QUESTIONS:

1. What will be the equity percentages between me and him be in the following situations;

    a. sale

    b. needed repair (after it is rented and he can afford to pay his proportion(

    c. generated rental income

    d. tax write offs

2. If I end up supplementing mortgage payments how much does this offset future equity vs not supplementing?

Any insight is helpful. Thanks!