In San Francisco, every downtown office space I've been in has had cleaning service included in the rent and a building manager who looked after fixing minor issues.
For one off or infrequent services like cubicle assembly or wiring new Ethernet ports, an uber model works, but cleaning you probably do every day and you want a contract to outline exactly what you want done and to negotiate a lower price.
I'd be as huge fan. Running a small office with 15 people in it takes a lot of work. I'm definitely not above mopping the floors, doing the dishes or hanging whiteboards myself, but it's more effective for me to pay someone to do this while I spend my time working on the product or helping someone else.
I can't speak for the size of the market, but offices we've looked at in LA don't often include cleaning services, and there are a lot of small offices that couldn't justify a full time person for this role.
I would like to be able to get the same person most of the time.
The services that would be important to consider doing are: