Depending how long you were going away for you may not need to board it.
We feed ours every other day and you could stock the tank with plants for it to graze on and just have someone pop by to feed it once or twice.
I'd imagine that would be fairly hard to do, you couldn't move the tank and any other tank would have to be set up for a while before yours went in there, you'd either have to have two of everything or a very willing person who already had all the equipement.
most exotics shops will already have some form of it setup but it would not really be acceptable conditions i dont think. I cannot think of a single place ive seen terrapins for sale in worthy tanks/setups etc.
But maybe youve just found a hole in the market lol!!
but if i were you i would just stock the tank as said above with plants, if youve a nasty streak about you and you dont mind it, you could buy some lil cheap neons, i am sure your turt would enjoy them once he caught them too...but thats not for everyone's liking, i never did it but it would be an option i think
mine are now in the pond so I don't have that trouble anymore buts its a question of everything being on timers and someone comming in to check/feed etc either that or don't have a holiday theres no easy way I have 6 torts, 2 turtles, 2 guinea pigs, 8 birds, 3 hens plus a tropical fish tank you try sorting that one out:gasp: its a good escuse for making freinds you might even find another reptile/tort etc owner near you and can return the favour. I recentley had 9 torts stay while their owner had a weekend away but that didn't need a tank/filter etc I'd offer but don't have a second set off equipement.