Entry-level FCS head coaches are making about $200K per year. The entire staff is probably about $1M. Not sure what extra staff would be required that is not already part of the UVU athletic department. Probably at least a couple of football operations personnel and a couple of support staff.
FWIW, a $50 student athletics fee would give the AD an additional $2M per year. Also, $2per year is likely a relatively tiny amount in the context of the University's overall budget....and even a small portion of its marketing budget.
Many FCS football schools share weight-lifting facilities with other sports. Some relatively inexpensive upgrades to expand capacity would likely be more than sufficient.
SUU's stadium holds 8,500 seats. Utah Tech's stadium holds 10,500. Utah Tech's 2017 stadium upgrade, that included a new football field, new track, practice field, new locker rooms, concessions, restrooms, ticket office, and doubled attendance from 5k to 10K, cost about $35M So, probably less than $50M for a nice, smaller stadium project.
But, I like the idea of UVU leasing LES temporarily during its start-up phase to give time to find donations and financing for facilities expansion capital. But, the capital expenditures could be well worth the marketing and exposure benefits directly related to a Division I college football program.