Hi @Kath5, as you are in the UK the best people to approach are Admiral (subject to some points below). They started doing home and contents insurance specifically for AirBnB hosts about 2 months ago and we were one of the first ones to take advantage of it as our previous policy (with a different company) was coming to an end. It cost us in total about 25% more than the previous policy but we did add some extras re the contents. You need to quote "Host" when you speak to them - you can't arrange it online - and make sure they are aware you are an AirBnB host. We found it all quite easy.
Some points to note:
1) Homes can only be rented out to guests for a maximum of 90 days per year. This will be no problem for occasional hosts or where you are not doing it all year. But the time limit means Admiral's policy add-on isn't suitable for people who regularly rent out their properties for extended periods. For that you would need a commercial guest house policy which is usually more expensive.
2) It can cover more than one room. The number of adult paying guests occupying your home at any one time cannot be more than double the number of bedrooms (for example, no morethan 4 adult paying guests in a 2 bedroom property)
3) The most they will pay for loss or damage to high risk items causedby Theft, Vandalism or Malicious Acts, or Accidental Damage while your home is occupied by paying guests is £5,000 or the amount shown on your policy schedule, whichever is less, unless kept in a locked securely fixed safe or removed from your home.
4) You don't have to contact Admiral every time you rent out your home or room on Airbnb. Once you've added the cover, you don't need to keep contacting Admiral to tell them you have a new booking.
5) Cover is only available to Admiral Home Insurance customers, and you have to add it over the phone. This means you can't simply buy Admiral Home Insurance online at your next renewal and be covered for hosting.
6) Second homes and holiday homes aren't covered; it must be the main family home.
As to tax, you should declare the net profit minus depreciation (10%) and costs for breakfast, newspapers, sheets, towels etc (keep the receipts!) or anything else you spend specifically for the rental. There is a £7500 rent a room tax relief - https://www.gov.uk/government/publications/rent-a-room-relief-increase/increasing-rent-a-room-relief - but you will probably need to complete a self-assessment tax return. If you have any concerns or questions it is best to ask an accountant who knows about tax issues.