A regular cleaning service is something I see rather problematic:
if the guest rents a full unit or a private room. You have no right to enter it, if you are not invited to do so. What they do inside till checkout is their affair - as a guest, I might not wish intrusions into my space under the guise of an extra service. If I want my bed made and the bathroom moped, I'd book a hotel. If I want to be in that bed at odd hours and maybe leave a transparent contact lens on the side of the sink, I'd not book a hotel.
If you are not close to the place you rent (like your own place furing a longer absence), you can't clean for your guests yourself. That means staff, maybe not your employee but a friend, a cleaner paid on invoice or more probably in black. What happens, if the guest claims something is missing and the cleaner denies it? May not even be a theft claim, just the unseen contact lens swiped into the sink during normal cleaning.
If you are in no official relationship with the cleaner, no insurance will cover it.
On long stays, I guess I got only 5 stars anyway. People prepare long stays better, they compare and book a place to stay comfortably for a longer period, whilst they may look only at the price tag for one or two nights. It's more important if you have a socket for your phone charger beside the bed and maybe some more for the laptop to watch films whilst playing on the phone, and a fan or whatever. A place to sit and prop your feet up, a kitchen, big or small, where you can cook comfortably whatever your level of competence, enough cups and glasses, to allow not to wash dishes every day if so inclined, a place and equipment to make yourself pretty / presentable and to check the effect, especially if it's a professional stay - all these things are noticed daily and will have more effect on the stars than a cleaning service.