If that business is selling your time to someone else for a given set of skills do that and ignore the hype machine that touts passive income as some panacea that will cure all that ails you. 

It dosent even have to have a washing machine for example. 

That extra separation of the sales arm from the larger mortgage machine instills more accountability and competition into the process. 

The only reason I would include washing machines and dryers is if all comparable rentals included them.

I started renting out the rooms to friends and my basic strategy is to just charge them a flat fee.The cons to this approach is that they are able to take long showers and use the washing machine a million times a month but still pay the same amount.

Around here we can take them to a larger branch of a bank and they have a machine that counts it for you, just dump it in!

Set up has 1 detached unit with its own water heater, and 2 attached units with two water heaters, one of which supplies water for both attached unit washing machines.

The caveat would be the less common specialty items (apartment size units, fridges that have to be within an exact dimension etc..) where there isn't really a steady used supply of machines available.

Smoke gets in everywhere, walls, baseboards, flooring etc,,, there have been a few times I kilzed all the walls, tore up carpet and treated floors with a special enzyme treatment and brought in an ozone machine. 

I may be able to hire someone to come in daily and clean everything on a daily basis for an hour or two, but I'm not sure how to handle emptying the machines, or refilling a change machine, etc.