I have a small janitorial and housecleaning service. My main business is window cleaning, but the other 2 areas come in handy.
I know exactly what you mean about the last minute cancel and losing the payment for that clean.
The only fair thing that I can think of is to charge an initial clean fee when they return and you in essence start over or at the minimum have a bit more time involved in the return clean.
In addition I hear you when you say that their time slot is reserved and when that slot comes and goes with no monetary reward yet it still must be saved it is a loss for you.
You may want to consider what policy would be the best.
I have heard some contractors say that when their clients leave for vacation they do a "deep" clean.
Extra things that normally would not get done. (Refrigerator/oven clean); ceiling fans; carpet /floor scrub, hard to reach areas, etc.
I think you should consider all these things and adopt some options so your income will remain steady. Surely your customers will agree to a policy you adopt.
Hugs,
Texas girl
