The investor would get 30% net, rest paid 50/50 until the down payment is repaid then 50/50 thereafter. 

I'm an investor and Real Estate Investing Coach who specializes in Wholesaling, Multiple Choice Offers, Flipping Tax Deed Land Lots and Seller Finance Rentals where both the Seller and the new Lease Option tenants pay me, leaving me with a little cash flow while I wait for the mortgage balance to go down and the property value to go up during the 1 to 3 yr Seller Finance period.

Since you have a substantial amount of savings, I would probably aim for one single-family house, where you will live, FHA first-time homebuyer if you can make that work, save the rest of your cash, find employment, then start looking at the next place.

There have been distinct periods that I recall where Memphis was booming: 1. 

So over a 20 year period, that's maybe $8000 in taxes (which is written off annually anyways).

Their are usually seasoning requirements or a waiting period of at minimum 90 days to obtain a mortgage.

After I get the construction loan funded I immediately pay myself back (except for the land) and pay the rest of the construction expenses with the hard money funds.  

there are so many 2 family homes with all kinds of configurations there. the best you will be able to do is try and match the rest of the house, square foot, number of baths etc. you may be able to get away with a 6 bedroom house as a comp, 3 and 3. i know i am having the same trouble with a house i own in PA, its under contract but when they came back there was no exact comps to mine, we are in the process of fighting what the appraiser came up with right now, they came up with $38,000 under my list, but i know i priced it right based on price per square foot and whats in it, 2 family with 3 and and 1 bath each. try averaging what a 2 family sells for per square foot, that should give you an idea. then sell it to me for 100,000 less - just kidding, but you can let me know if you do decide to sell, I'm in the town next door.

I think that was vital to the survival of our first property. nice. did the rest of the 70k come from a bank or was it private investment?

This assumes that the MAX seasoning period before I can do the refi. is 6 months I would then use this $21,000 to purchase another property as a Rental property , but this time ...