The idea is that you pay an upfront option fee (1 to 10% depending on the owners market/motivation/competition) to purchase the house later at a predetermined price while you rent it, usually at slightly higher market rents (& you may be given rent credits for monthly on time payments which will be used for your closing costs at time of purchase).  

My thought would be that I would bring a relatively small cash contribution but give most of the overall appreciation to the flipper, in exchange for the experience/knowledge that I would be earning and the promise to be the guaranteed first offer with predetermined price range when going to refi (maybe even with private hard money on family-member-terms).

More Financing options Lease-purchase agreements: A lease-purchase agreement allows the buyer to rent the property for a set period of time, during which they have the option to purchase the property at a predetermined price.

Investor buys home with pre-determined sale price to tenant-resident (ultimate home owner) with targeted purchase of 6 months to 3 years.  

Automatically add money to an S&P 500 ETF into your Roth at predetermined periods spread throughout the year to surf off both gains and losses.

People simply won't easily buy a house with previous hystory of crumbling foundation even if it is fixed... or "claimed" to be fixed.The 70% rule also doesn't account for the projected time it takes to flip a house.And no... your predetermined "holding cost" incorporated in your 70% rule is not it.The 70% rule is a death trap and is a sure way to derail your business.Also, if we are both interested in the same property, and you give a 70% offer, you will ALWAYS be beat by me that will ACTUALLY give the highest possible offer I can make. 70% rule focuses on being "safe" and will have the effect of not getting many deals.The right method focuses on property determined risk analysis to leverage "being safe" with the amount of allowable profit (for that safety margin). 

Cj Juan You can't hit anyone with a large bill until they approve it, half of my COs aren't fixed price, they are T&M based at 15-25% markup, receipts and timesheets need to be approved on that day we do the CO, labor rates are pre-determined.

When you say "timeline", are you talking about reiterating pre-determined dates as stated in the lease (Rent due, grace period, etc.) or are you talking about a "pay rent or quit"- type timeline for getting the money that is due? 

The payments are dropped to 31 percent or lower of their gross income but at the end of the predetermined term, a large sum is expected. 

They cannot help you to analyze the deal according to your predetermined criteria.