There are two gotcha's (based on Swedish experience) your house company might change the rules not allowing rentals or simply deny you the right to rent because some renter broke the rules. The second one is the monthly fee, it is included in the rent but it can be changed by the management based on the building's need.

Another problem, at least here in Sweden, is that the law prohibits making an "unreasonable" gain on rentals so you can't compensate on bad periods by raising the rent.