@Sherry440
I specialise in long term stays (28 days +) and there is certainly demand for that here in London. You will need to do some research in your area to see if there is demand there.
However, I would also advise, if you haven't done so already, to look into tenancy laws before you list. I have read that in many US cities and states, that guests who stay 30+ days might be entitled to tenants rights, i.e. it is not that easy to evict them if they decide to stay and refuse to pay the rent. Airbnb doesn't really cover you for those situations, so you do need to look into this and make sure that the law is on your side and not vice versa.