Colleague at work is doing this - they live in New Cross Gate, so benefit from really good transport links. They don't reckon they are going to make a huge amount of money, once all the fees etc. are paid, but still worthwhile. Lots of hoops to jump through, apparently e.g getting an energy performance certificate, notify mortgagee, insurance etc. They are doing it through an agent - had Foxtons in and mentoned another, but can't recall offhand. Agents reckon not a problem with demand for short lets, even outside Olympics.