When you ring up see if they'll let you visit pretty much straight away, I went to look at two catteries and only gave them 'travelling time' notice. Here's a list of things to look for in a cattery from the FAB website.
http://www.fabcats.org/catteries/listed_catteries/index1.php * If also a kennels, do the dogs disturb the cats?
* Are the surroundings neat and tidy?
* Is there a separate kitchen for food preparation for cats?
* Were you made welcome?
* Have you seen the cattery's licence?
* Do the cats have individual sleeping accommodation? *
* Do the cats have individual runs? *
* Is there a shelf for cats to sit/lie on?
* Is there a scratch post in the run?
* Is there a gap or full height solid barrier between cat units? *
* Is there an interesting view for the cats?
* Is there a safety passage? *
* Do the cat units have the cats' names on?
* Are the units clean? *
* Is there any smell?
* Do the litter trays and bowls look clean?
* Is there a form of heating for each cat? *
* Do the cats in residence look contented?
* Have you been asked about vaccination? *
* Have you been asked about your cat's diet?
* Have you been asked about your cat's health?
* Does the proprietor seem well informed?
* Does the proprietor seem caring?
My boys went in a cattery for the first time when I went on holiday this year and they seemed quite stressed by it. The cattery I chose was lovely, top of the range accomodation and a lovely lady who runs it. One of them weed in their bed through fright (they've never had a single accident ever at home since tiny kittens) and when I went to pick them up Riley hissed at the cattery lady
I had a pet sitter come in twice daily for my next break and when I got home they were completely at ease and normal. I think for a long stay I'd probably go with a cattery but anything less than a week and I'm definitely going down the petsitter route in future.