high priced markets like west coast pricing might be 75 to 95% of note value..

its highly risky for most mom and pops to sell on sub to.. and its simply not a way for those without substantial wherewithal to buy property and keep the seller safe..

Some high and lowlights:- I had one tenant that brought German cockroaches in and then blamed it on me- Same tenant asking if her daughter can visit but failed to mention it was 5 more very noisy people- another tenant having constant loud arguments with his gf- tenant saved some of my stuff when the house flooded due to a pipe burst and another time during a monster rain storm.

The 10% vacancy and repairs, along with 5% capex in my opinion are pretty high. 

There are a high number of CPA firms that do not want to get involved outside of the FYI to their clients, and some state boards are saying that a CPA advising related to this registration is an "unlicensed practice of law" given it is not under Title 26 - income taxes - the only place where CPAs and EAs are specifically authorized to interpret law. 

Since the contributions have to come from the business income (PM biz) it’s not likely you’ll come close to taking advantage of the high contribution limits of a Solo 401k.

Like you we had 3 teams of two door knockers  2 for safety one women one man.. and we door knocked every NOD in our 2 mil MSA  all to boil it down to if we were very lucky to get 2 to 3 deals a month.. now we were a little different I only would buy very high equity deals.. and we leased back .. because as you state 99% don't want to leave.. 

Roads, water/sewer, city services, heck even just the planning for such is not a simplistic thing for all. 

I highly recommend going with a LOCAL LENDER ie in the same state, and preferably from the same area of the state you are looking.  

Condo's usually have high HOA dues which will eat into your cash flow.