3 dogs?

Hi all, i have 2 small breed dogs, but have for many years wanted a  border terrier. I know cc sites are fine with dogs, but a lot of non cc sites say max of 2 dogs. Do any of you have more than 2 dogs, and if so, do sites waver on the number if asked when booking? There are some border terrier pups for sale not far from where i live and am really tempted, but am worried it will affect going away in the caravan.