As producers, your budget is your foundation. It's the furnace that keeps your show nice and warm in the cold winter. If it breaks down, you could be in a lot of trouble. Ok, ok. Enough with the metaphor even though I may just be warming up ;)
It's never a bad idea to have someone else inspect your budget. Especially someone who has done a similar budget. This new producer did two very smart things. First, she asked for help and second, she listened to me even though what I had to say meant finding more money.
So if your producing a new show and you're very excited about your mastery of excel, make sure you take a second to run that budget by someone else. Give it a little check-up and odds are, you won't be sick later.