Almost exact same graph for single family home prices for same time period. 

I am in the process of purchasing a property, but carefully evaluating it during inspection period. 

It could be 80%, not sure of your exp or credit.  15% of 290k = 43,500 plus closing costs round that up to 50k, then you'll hold it during the rehab period let's say 5 months? 

This partner would get “dividend” in form of rent and then 50% of the value of the property for a min holding period of 10years.

Too many variables between now and then but that's a safer time period to look at this differently. 

20 years is a universal period of repose. 

You could ask to simply extend the inspection period and not delay the closing.

They usually have a team of trusted contractors for you to choose from, obtain quotes during the due diligence period on any issues, for you to make the right choice.

I currently have authorize.net but the merchant is holding 10% of my payout funds in "reserve" for 90 day periods.  

His book provides the knowledge you've likely already obtained, but also includes a state by state break down of if they are Lien/Deed/Hybrid states, applicable interest rates, bid method, information on redemption periods and references the states' statutes so you have a reference to keep yourself out of hot water.