Barbara, it would help to know the age of the house since, if it was new, that would help to figure out if the rough plumbers and mixed the hot and cold up somewhere. It would also help to know how upscale the house is and where it was located. But, even with all that, we would still be guessing.
I suggest that you go to your closest plumbing supply house and smile and bat your eyes a lot at the guys at the pick-up counter. Tell them that poor little you is all confused and you want the name and phone number of the best pro in the area. And then let them know that if they try to stick you with somebody that is going to rip you off, your big brother, Bubba, is going to see how many times he can coil a pipe wrench around the neck of the guy that gave the bad info. You probably do not quite have to be this crude about it but that depends on the neighborhood. Other supply houses know which plumbers are bad apples and will gladly steer you clear of the ones that give the whole trade a bad name. For that kind, which usually have nicely laid out and appointed showrooms, tell them that you will surely remember them when it comes time for improvements and the hot tub. You will have to go with your instinct on how to play this, but playing a bit of a game sometimes really helps.
Then call the plumber and tell him that you just want him to trace the plumbing to be sure it is right, tell you where all the shut-off valve are, and make sure that everything is as it should be and you know what to do in the event of a leak or emergency. You really should expect to pay somewhere around $100 for this if he really does a good job teaching you what to do and this will come back to you many times over if you do have a problem and remember what he said. I know that this will be a tough time financially with the move too but leaks and mixed up piping will cost you big time in water heating cost or the cost of water.