Hello CZ Mike and everyone in this community! My name is Jude and I am a worker-member of Hub City Cycles Community Cooperative in Nanaimo, BC
I don't have examples for you, but I have worked on sponsorship packages for athletes, discussed promotional materials for a similar campaign at length with some of the great folks at Makerspace Nanaimo, and done a fair amount of research on writing grant and loan applications. From this experience I have learned 3 things:
1: This gives you a margin to bargain with and at best results in a surplus! The precise percentage has to do with your audience and the number of zeros you're dealing with. Knowing the spending habits your audience and how much the outcomes you're offering typically cost (i.e. advertising/marketing for the business, educational programs for the community, transportation, etc.) will go a long way to determining a feasible margin without pricing yourself out of funding.
2: I've had great success offering pieces of leather suits worn by athletes for set prices based on size/placement of company logos. I like to offer three tiers with value added outcomes (i.e. hi-res photos for company use, video production, online product reviews... athlete sponsorship packages are my primary practical application thus far, these can be reworked for your organization). A number with a bullet point list of outcomes below it will immediately outline a range of options and begin to develop an idea of *why* one might want to invest more than the (perceived) minimum.
3: Given that the Bronze, Silver, and Gold levels of financial commitment are fresh in the mind of your reader, having perused them as soon as they opened your brochure, a simple outline of WHO and 'WHUD' (with some great photography to accompany it) is likely all the words you will need. What Have yoU Done is a great place to build confidence in your reader that you are exceedingly capable of following through on the commitments of each tier. Who you are could be as simple as your Mission Statement, perhaps with some detail on the individuals directly involved in the project, or the community you're serving.
I hope that helps. One year, a friend and I were looking for at least 5 sponsors at a $500 (silver) commitment level and ended up with 2 Gold sponsors at $1500, all because we had a great brochure, obviously ;) Unfortunately I lost the file in an un-backed up hard-drive failure...
It turned out to be a huge amount of work to pull off the Gold-level media-production and marketing outcomes we had promised for 2 separate sponsors, and a steal of a deal for companies who are used to paying much more for those services. Be careful to set your outcomes well within the capacity of your organization, it might just work beyond your wildest dreams!
I'll mock up a visual example and send it around, though my inDesign skills are a wee bit rusty of late.