I'll trade losing a few hundred dollars to keep good tenants over potentially losing a month of rent during turnover and higher maintenance costs associated with demanding tenants and lost of sleep. 

If I spent a hundreds or thousands of dollars and I got any kind of a marketing campaign, unless it was extremely well chosen to help me and not the seller, it would be reflected in my reviews to that place

I'm sure there are hundreds of posts about picking the right tenant, and I can't stress that enough.

Quick jobs that can raise a couple hundred for gas/food for the week.I have never failed, I just needed more time.

I was a lending exec for 25 years and made hundreds of HELOCs in my career for real estate investment purposes.

So that should be your target Seller: Ma and Pa, "salt of the earth" type people who are willing to let you take a sawzall and chop saw to their asset worth hundreds of thousands of $$$.I think it's doable, but don't be surprised if it's not as easy as the rosy picture you paint. 

It’s common and something that’s been around for over a hundred years .

I'm an avid runner and have ran hundreds of miles around this neighborhood through the years.

Furthermore, dozens or hundreds of hand-written letters is very time consuming. 

Heck, I've seen plenty of properties in my market sell for tens, even hundreds of thousands of dollars above the appraised price, so appraisals often don't even influence sale prices, let alone rents.