Should not have to bring a compressor and they should provide you with nebulizer (cups) though you'll want to keep an eye on them -- since there's no way to clean them, you may have to insist on a clean set each time -- some places like to leave them hanging on the wall and reuse them all day long. I did have some spare sets, unopened in our suitcase just in case, along with albuterol/atrovent in case the RTs got delayed and we wanted to start DS' vest and keep on schedule.
We also had along DS' vest, but hospital policy preferred not to use our equipment. They had one time use tubes for the machine and vests as well, but DS was having issues with things looking different, being different, so we ended up using his regular vest because is was black and the one time use one was white...