In Helsinki each building is owned by a maintenance company - a company that takes fees to cover basic expenses, but which isn't allowed to generate a profit. You don't buy a flat, as such, instead you buy shares in the holding-company.
In short all flats/apartments are cooperatives, but still profit occurs when they're bought and sold. The structure and profit/loss are unrelated.
There isn't really any law that disallows housing cooperative from generating profit per se , but generally there isn't any reason for it to do so. Some very old ones actually do pay dividends and do not ask fees from owners, but that usually requires that the cooperative is debt free and has a way to generate income (i.e. owns some of the apartments/business premises that it rents out) and that it has saved up enough to pay off planned maintenances.
In short all flats/apartments are cooperatives, but still profit occurs when they're bought and sold. The structure and profit/loss are unrelated.