Foundations that are required to give away 5% of their profit by the IRS, often state the amount of money they expect to give away in individual grants. If the grant maker provides a range, make sure your project budget is presented within that range. Your proposal runs the risk of being tossed out if it does not meet those basic criteria.
If you take the time to conduct research on the funding agency, especially looking at their IRS 990 Tax Forms, you can see what past funding levels were made by the grant maker. If your request is too low, your project may be seen as less deserving; while too large a request may tell a funder that your organization does not have the capacity to carry out the work. Use the information gathered from your research to frame the application and budget for specifically to each funding agency, based on its past awards and published grant award amounts.