If your bunnies had been housed indoors previous to coming to your home, you will need to house them indoors until spring as it is now too cold outdoors at night and they would not have had time to start growing their winter coat. There are also benefits to having indoor rabbits. You spend more time with them which helps socialize them with people better, as well as having a chance to develop a much closer bond with them.
If they were previously housed outdoors and are used to it and have had time to start developing their winter coat, then keeping outdoors is fine as long as their housing contains a mostly enclosed area with enough warm bedding such as straw, to help keep them warm when it is chilly out. Though if they are very small rabbits you will need to check on them to make sure they are coping fine with the cold. A snugglesafe is a good way to help give them an extra bit of warmth when needed as well.
I would not advise letting indoor rabbits outside for too long or outdoor rabbits indoors for too long after temperatures have dropped. The reason being is that their fur grows according to their usual climate. Indoor rabbits will chill quickly if let outdoors for too long, and outdoor rabbits can overheat if brought inside for too long and it is too warm. So if they are let out of their usual climate, you will need to limit the time and check them regularly for overheating or getting chilled.
If you do house them indoors and allow any free roam time, remember rabbits are diggers and chewers by nature, so some rabbit proofing will need to be done, especially with electrical cords.
http://bunnyproof.com/
If your rabbits are young unneutered males, remember that around 12 weeks they can start to get hormonal and may start to fight, in which case they will need to be separated until you are able to get both neutered and have waited 3-6 weeks post neuter for the hormones to settle before attempting to rebond them.
You will also want to check their sex regularly to ensure one bun doesn't have a unexpected change of sex(which does happen) and you unintentionally and potentially end up with a pregnant female. So it's good to have a vet checkup by an experienced rabbit vet to verify their sexes and also get their vaccinations done at the same time.
This is also a good UK based rabbit care site that may interest you.
http://www.therabbithouse.com/
the positive news is that we got two more little bunnies (both male.) Called Bunny and Bear. We picked them up this morning and right now they are kit side In my old rabbits disinfected hutch. But I have set up a hay basket, litter tray and bedding in the bathroom and am wondering whether I should move them inside as England can get pretty chilly. What do you think? I'd prefer to have them inside but need some confirmation on whether it's a good idea, thanks,
