Finding the Right Babysitter

The time has come that we have started to look for a babysitter for the girls. It will be nice to have a night out every once a month or so but also with our work schedules getting only crazier it is good to have someone that we can count on. Sure we have lots of friends here that watch the girls for us but I don't want to strain any friendships over it as it has happened to me (the one being strained) in the past.

So with this babysitter thing officially decided I need help! What questions do you ask your potential babysitter? I know obvious ones...Are you CPR/First Aid certified?  Do you have any references? etc. But what are some good ones you have used or can think of?

We are also looking to go through Care.com to find one but has anyone else found one a different way? I am not looking for a teenager in high school because if for some rare situation I need them during the week and I'm at work til midnight I know they wouldn't be available.

I am excited to have a more permanent sitter that the girls will get used to and have fun with but let me tell you this overprotective momma sure is nervous! Makes me wanna put some nanny cams all over my house when I leave!

So please pass along any advice you may have!