I know the rules can vary greatly by state to state and I intend to add certain provisions to be reviewed by an attorney but I am curious to see what a good agreement for both a seller and an end buyer encompasses.

@Josh Caldwell There are plenty of companies that can do relationship marketing just as well or better than MLM's, they just don't rely on it like MLM's because they have real products that people actually want in the real market.

All the rules regarding tax sale can vary tremendously by state and even local jurisdiction.

VA caps vary from city to city.

I know it will vary by location and by each investor but what numbers do you like to see when analyzing a deal?

I would imagine that the details of how builders structure partnerships vary based on the specific nature of the deal and the parties involved (how extensive is each person's track record, how much money will the investor be expected to invest, how much money are you willing and able to invest to show "skin in the game", etc.). 

Something else to consider if relying on HELOC.

I have spare time quite often, but it always varies week to week based on the weather and seasonal business patterns. 

(Your mileage may vary.) 

Each state has varying real estate laws and practices.