Ah yes. The Laundromat that is run by part-time help and makes hundreds of thousands of dollars a year.
Do the Part-Time help handle all of the cash and make deposits as well? Unless it's credit/ debit card only there is going to be cash. A "Card Store" usually has a kiosk for the customer to transfer cash to a store card.
What about repairs? Is there a maintenance man handy they can call or does the owner make the decision? Personally I do all my own maintenance.
Most owners I know are doing well because they have bought from the absentee owner and became the active owner.
I would plan for at least 15 hours a week and those hours could be at anytime. Like 7am when the attendant doesn't show up or 11:30pm when someone calls about a machine that didn't work.
Don't get me wrong, they are a good investment when properly vetted and managed, I've been doing it for 7 years, but be careful with the word "absentee". That great manager that the current owner has might decide it's time to move on or retire when you take over. Now you are setting the shifts and hiring attendants.
I consider each washer and dryer to be a "door" that people rent for about 30 minutes at a time. The best part is if one is closed they just use the one beside it.
I've trying to figure out how I can get some of the millions that developers put towards an App for Laundry that fails when they could have paid cash for a few stores, hired a great manager and had a decent income for 15 hours a week.