Just having chickens can attract predators into a yard they've not gone into before, so if you know that you have racoons nearby, assume they will eventually find out that you have chickens and will want dinner.  Build your pen accordingly, there are a lot of suggestions on the Coops thread.
I have a pet sitter who I pay a small amount to check on them when I'm gone.  Additionally, my neighbors let them in and out but they also spoil the girls and I've come home to scratch a half inch thick on the ground and pasty butts, so we'll have to talk to "Granpa Dan" about spoiling the girls . . . 
Chickens can spend a few days confined to small areas but too much confinement can cause infighting and cannibalism.  
It's tough, I know.  I almost sold my girls simply because of the pet care issue when I wanted to leave for a while.  I decided to do the best for them that I can and take chances.  I've had mine outside now for seven months and haven't seen a 'coon even though I'm less than 100 yds from the banks of the Colorado River, but I have a dog and she runs around the yard.  I've heard that even having a dog in the yard creates a smell that keeps coons away.  I'm not planning to take chances though.  They have a secure house and will have a pet sitter when I go.
I found mine, a former chicken-raising 4-H girl (now a young woman) at my vet's office.
Mary