Dh & I used a Pet courier service that did everything for us. from the littlest thing to biggest like getting my cats to the airport & then delivering to our door in the UK. I will tell you this much it wasn't cheap! I want to say between $2000-$2400 thats everything though, also this was in March 2005. the essential paperwork, an Airline approved cat carrier per cat, each cat's plane ticket, flying my cats from Indiana to New Jersey then to Gatewick then delivered to our house. but worth every penny to us. when my cats got here I felt a bit more settled. not everyone cant afford this I know, that was our honeymoon fund. I would tell you bit by bit what everything cost but I don't have the paperwork for the service we were charged, but we don't have it right now. that paperwork along with alot of other Important papers are at the Home Office with my ILR application. whenever we get that back I can tell in details what everything cost in a PM that is if you would like to know. I don't know how much Quarantine costs here in the UK. sorry I cant help you with that.
Like a few other have said I would never allow my cats to go into quarantine here in the UK. if possible I would do my best to find someone you trust or a nice kennel to put them in for the remaining time left, before they come over here to the UK. than put your pets in to quarantine over here. I have heard to many horror stories about them here not to mention the outstanding price tag it would be as well.