When I was reading your post on the other thread about all you're going through I had to laugh! We're definitely different!

You are the city mouse and I'm the country mouse!

Here we get stuff like that in our basements and attics all the time. And I don't think we even have companies around here that will come take care of them. We have to handle them ourselves! Traps work well, but I can just picture my husband heading up to the attic with a stick to take care of the problem!
On a serious note, though, yes they do make a mess and you'll want to clean up really well after they're up there but I wouldn't hire someone to do it. Just wear some gloves (and maybe one of those dust masks if your attic doesn't have good ventilation) and clean up what they've left. Rats are worse because they actually climb in and out and on everything leaving dropping and urine wherever they go. Raccoons tend to stay on things and are usually just looking for a warm home, not looking for whatever they can nibble on.