Used trailer question

I am looking to purchase a used concession trailer and I have found one that fits into my budget. What questions should I be asking to the current owner? I am thinking of ones like is it currently in use? In what counties has it been inspected/certified in? Current menu? Weight? And next, should I take that info and any pics to my HD and talk w/ them to get their take? Thanks for the help,

Kevin

What kind of trailer is it, BBQ? Hot Dog? Ice Cream? Funnel Cake? What? Give us more details!
What are you going to produce in it?

how bout.. sizes of the water potable and gray tanks..year of appliances if any..if it has a hood system has it ever been inspected? cleaned? by the way if it does have a hood system take the filters down check to see how the grease is under them(or over so to speak) you may want to check the ceilings too.. when I was looking I found what I thought was A good rig ..but I noticed that the ceiling didnt look quite right. when I pushed up on one end ......the water just ran out of it...no thanks !!

Yea, those would be good things to know..my partner and I have have a bbq catering business, so we are well versed for serving up to about 500.  We have done several Relay for Life events for the past 6 years of fried foods, (Oreos, Honey Buns and Pickles) and we are thinking of expanding to this...so we are looking at a trailer to help out...This would be used for fried foods mainly, but if it comes equiped w/ a griddle, then maybe sausage/brats (depending on the event). Thanks again,