I dont know cresteds, but beardies are Alot of work, If you have a baby, they need to be fed 2-3x a day, plus salad, An adult can be fed every few days with live food, and daily salad.

Give him lots of baths before you go, and have the person mist his head, If you can teach him to drink from a water bowl, it would be great for hydration. And make sure temps are stable, Lights are good, and you wont have any problems.

For me, I usually bring my dragon anything i can drive to, pack up a small tank and go, but germany isnt that easy. I had my vet look after him one time, but expensive. Maybe a fellow beardie owner can take another in for a few weeks. adding another isnt a large addition to there schedual, just a extra bowl of worms and greens.

Anyway, A baby would be next to impossible to leave on vacation with someone to look after it unless the dragon lived with them, A adult would not be as big as a problem.

But if you can figure out a solution, and facilitate the care, Beardies are WONDERFUL, they really rival furry animals in affection. Kinda like a cat, they like occasional attention, but doesnt mind being alone for awhile.