invoice customization

As an Assistant Facilities Director, I would like to be able customize an invoice to show a date range and then a flat rate charge for that date range of use.

When a group submits a request why is every date listed as its own request (ID)? I am sure this is how it is designed for the purpose of better tracking, but on our side, requests are not treated that way so it makes it more difficult when they are listed as separate requests instead of one large one.

For example, a soccer club requests a field for 3 months of use. The group submits all the days they need for practices and games (30+ recurring dates). According to our purposes, this is one request not 30. We do not invoice charges by the hour because it would simply bankrupt the community group so we charge them a monthly or seasonal rate. The group still needs to submit all the days for calendar purposes but the invoice should not have itemized lines for each day's use. In some cases the invoice would be 5-10 pages long for the 30+ dates they request. We should be able to customize the invoice to include all the ID' #'s in one date range and change to rate charged. In this case, a flat rate.