[.:4:.]

Now im talking probably well out of the realm of financial viability. But there are companies that purely offer serviced offices. Small businesses that do not need a full office space rent just an office. So multiple small companies in their own rooms, communal kitchen, photocopier etc. If you need a meeting room for whatever reason you just rent one for the time required.
All the places like that ive done work for supply inteweb connection. So theres a few options if you chose to pay, like cleaners, if you dont have a receptionist, you can use theres to forward calls or take messages, if you dont want to supply furniture often they can. But its only really financially viable if youre running a small business and turning a profit.