I do this by doing open house showings.

You're just making profits for the lender.You could also sell #2 if you bought off too much house. 

You're gonna get your houses robbed a lot.

Instead though, I don't want to sell it but use the refinance money to buy more, I've been thinking about buying back taxed houses in the area. 

don't be afraid of better markets in ohio like columbus. depending on the capital allocation buying old houses and having to renovate is not the only way to drive value. build rent refinance repeat and build to rent are both very strong market drivers as well and you can traditionally get infill land in areas like columbus in much better locations than where you buy.

For example, houses where the homeowner needs help and may consider selling to me. 

House is worth 260k and we owe 200k on it.

I would recommend doing a House Hack or duplex to 4plex hack. 

@Christine VasquezHow high can housing prices in the City of Detroit go?

Purchase price: $211,000 Cash invested: $50,000 Purchased this house for $211k eight years ago.