I would approach it differently, you could perhaps look for other reptile people in your area with the experience to care for them while you are not able and work out some sort of agreement (on paper) to a mutually agreeable understanding. I have seen this in my area where a snake has been cared for by someone else for 2 or 3 years and the owner kicks in a maintenance fee for food and such every month, the ones I have seen about 8$ to cover food and power. Extended boarding of sorts. This usually starts with finding a understanding person in your local community. The times I have seen such a thing ended in fast friends. It has the potential to go south as well so be careful.