Here are some suggested improvements to setup fees on SaaS plan products:
* Allow setup fees to be edited after creation
* Allow coupons to be applied to setup fees
* Allow calculation of affiliate commission on setup fees
* Option for prorated setup fees on plan changes. If someone upgrades to a higher plan, currently they will be charged the full setup fee. I'd want them to pay only the difference between the setup fee of their current plan and the new plan.