Before you target 5 different cohorts it's better to target the context of where the ad is shown. i.e. web content normally already has a category and people reading an article about cheap flats in a city might be very much interested in renting or buying a flat. By collecting signals on a user you might only get that interested after a longer time, if you even have a profile, and by the time you pick it up they might have a new flat and are no longer interested.