Go to Etsy and search for "rental property tracker," and you will find hundreds of nice spreadsheets to track 10-20 rentals, usually for under $10.Software has extremely helpful features like online payments, marketing syndication (click a button, and your property is advertised on multiple sites), electronic document review/signing, maintenance tracking, and owner reports.

I would just point out that you must make clear you are selling the interest to purchase, cannot advertise the underlying real estate (as that would require a license).

Advertising (photos and listings.) turn over costs, snow removal, and those kind of things.

Go to Etsy and search for "rental property tracker," and you will find hundreds of nice spreadsheets to track 10-20 rentals, usually for under $10.Software has extremely helpful features like online payments, marketing syndication (click a button, and your property is advertised on multiple sites), electronic document review/signing, maintenance tracking, and owner reports.

They will not offer that (instead relying on your advertised rate), but they will be willing to pay what you're asking without fuss as long as it is below that high threshold.

Do you advertise and show properties BEFORE a tenant moves out?

I've seen people on FB advertise cold calling services which seems interesting.

Now they have exchanges, which are still not as secure as they are advertised to be by the operators. 

You just advertise that free pool/landscaping is included. 

It's only 110V but would be nice on the property advertisement for potential tenants.