I suggest units like those above because they are very portable and are alot easier to store away in a corner plus she wont have to worry about dealing with hot coals at the end of an event. Is there no space available for her to store a trailer of any size?
My grilling trailer (The chicken Coop) would be ideal for something like this, it's built from a traffic light trailer so it already had gullwing lids on both sides and only needed a few racks put into place and exhaust. I don't have any photos of the finished build all tarted up but I do have a few before, mid way and in action as it was completed the day before it's first use...minus the paint ,new wheels and finishing touches but it cooks like a dream. lol
Consider building something with doors if you want to go the charcoal route.
Slappin that bass like some delerious funky preist!!!
UDS, Half Pint (Mini UDS), Weber, ProQ 20, Kegrilla
*250 gallon cooker- 'The Meat Beast!!'*
British BBQ Championships
Grand Champion 2008
British BBQ Society - Southern Championship
Grand Champions 2009