Heya!
I've actually been petsitting for 6 years now, almost 7.. (since I was 10). I ALWAYS take someone with me! Wether it's my older brother, Dad, Mom, Aunt, etc... I would never go into a job alone.
I always meet the people I'm petsitting for BEFORE I start a job.. I haven't really stayed on top of this topic.. but, I'm sure you've already gone over that.
I think it's great that you're starting to do this! Just make sure you have insurance... there are some weird people in the world who can try and sue you for their dog peeing on their carpet.. lol.. Just be careful and always keep a watchful eye.
I also have a sales policy that goes over all insurance/ liability type things and the customer must sign and agree before I start the Job.
I always take the money before hand too.. I've been stiffed quite a few times and I don't want that to happen to you.
Just be safe and careful!! Esp. with dogs, you don't only have to be worried about the people.
Best of luck to you!!
~Lacey