You need to research potential areas to buy in, current and previous sale prices, sold prices and rental demand and then you need to set about finding a property that ticks all of the boxes and is going to deliver the kind of returns that you are looking for.

Although you can pretty much turn any property into an investment property if you buy at the right price and in the right area, it is much easier to see rental returns on 3 and 4 bedroom houses, because not only is there more of a demand for this type of property, but you also have a much extended period of how long they will probably rent for.

Flats and studios tend to have a high turnover rate, due to the type of tenants that you get in there, but when you are renting to a family, they will tend to hang around much longer than single professionals or similar that might probably be moving on to different areas due to jobs etc.