Hmmmm - major differences in cooking offsite; let's see
- your pans won't fit in their oven/your salad bowls, etc. won't fit in their fridge
-they have an electric stovetop and the temp won't get high enough to do your final searing
-You've asked them beforehand to clear the countertops and empty the fridge, only to arrive and find the fridge filled with beer/wine, and the countertops full of presents (housewarming, christening, shower, etc.)
-Their dog(s) won't stay out of the kitchen - they're always tiny little yappy dogs and you're scared to death you'll step on them!
-Some inebriated guests want to help you in the kitchen
-Some inebriated guests trip over your gear and break your good pottery display platters
-Some inebriated guests hit on your married with children server, to the point where she wants to leave mid-service
-You set off the smoke alarm while searing off
-And the worst - Of course, you've arrived early enough that you can park up close to the house to offload, only to find you're blocked in when you're ready to leave
-The patio party for 50 has to come inside because all the lights have attracted every bug in a 5 mile radius just as you're ready to serve the dinner buffet; of course there's no table big enough for all the food, so the buffet line snakes around the table, through the kitchen counters, and onto a cutting board placed strategically over the sink!
-You've done 150 baby lamp chops for passed hodo's for a wedding party of about 60, and one guy (guess who's 'inebriated'!), is grabbing handfuls off the tray
I guess my most favorite word for off-site jobs is - improvise!