This info comes with the usual caveats:
always consult a professional
past performance does not imply future returns
do not take internally
make sure your CPA know the what the meal/hotel rates are for DOT TIMED LIMITED workers (pilots, long haul truckers, etc). For example, regular folks can deducts 50% of meal expense, but DOT TIme Limiteds get to deduct 70% (I think those were the rates last year... may not be exact but you get the point). I have found several tax folks that give me a blank stare when I mention DOT time limited.
You might also look at the difference between standard tax perdiem rates (what the IRS says a hotel room and meals cost per day) for the city's where your overnight. In some cases, using the standard rates will let you deduct MORE than using your actual expenses. Warning: you cannot mix per diem rates in this town with actual costs someplace else. You must choose one method and go with it (I cannot remember if one can mix perdiem for hotels with actual for meals or vice versa.... talk to your pro)
If you are REALLY bored or an incurable insomniac, you can order IRS publication 17 for free and read it. It can be a bit confusing, but it may help you quiz you CPA about your particular stuff. Or you might find think to yourself, "heck, i can fly a zillion dollar plane, maybe I can do this myself." I did, and I do.
Hope this helps