I successfully converted a 2400 sq ft single family 3 bed/2 bath into a 2800 sq ft, two separate 3 bed/2 bath ADU, by converting a two car garage into livable space in Santa Barbara. 

Bought it for $95k off market, planning to put in about $43k and sell for $190k.We walked through twice and the seller told us there was no basement and no crawl space. 

It would be cool to see things like this succeed and grow into things like multi-use developments grow up around modern mass transit access points.

I have a retail/office space that is the first floor of aMulti use facility I own.

I would suggest trying to find Single Family homes where you can have separate living spaces (walkout basements, separate entrance) that way you get the comfort of a duplex without the price. 

Between the rental units I own and the ones I manage through my property management company, there are almost always some things that pop up for the first month or two as tenants settle into a new space. 

Strata fees and people not wanting to share space with other people is causing a significant drop in prices.

Is there any way to do a value add, you mentioned the basement. is there any living space down there?

Have them not anything wrong (carpet condition, paint, yard, etc.)I just helped with a lease of some commercial space for a non-profit I sit on and their leasing agent didn't do this.

For a linear array of 14 spaces, including installation, I was quoted about $28k for full cantilever (posts at the very end) or about $25k for semi-cantilever (posts offset from the end by 7.5'.