It is very important to be familiar with the budget for the event. In some cases the budget is derived from a specific fund with a limit on total spending; sometimes the limits are applied to specific areas  ($1,000 for travel, $800 for support services, $400 for support materials, etc.) Determine whether you have a budget, the total of the budget, if the budget is line specific, or bottom line responsible and if there is a time limit for expenditures (expenses need to be incurred by when, and bills need to be paid by when). It is important to be prudent in committing funds because there may be unexpected charges; expect an overrun of 7-10%. Note we do not reimburse for private planes, but may reimburse a portion that we can determine is fair based on commercial airline prices, or if close, car service charges. Track all expenditures and submissions, and monitor the audit sheets that come from the Controller's Office as they arrive to verify that all has been charged as planned.