If the vapor barrier is going to be covered up, then any old tape will due, if it's exposed and you don't want to spend a lot of money, then I would go with packaging tape.
Has anybody had any experience with Conestoga's RTA cabinets? I know they are made in the USA and they are all wood, no particle board. I am getting a quote from NorthernGraniteandCabinetry.com for my kitchen and looking to find out any information I can get.