i do web/email hosting and am in a similar situation with my customer domains. however, i'm an opensrs reseller, so i usually do the actual domain registration and renewal for my customers as their registrar. if customers don't want to transfer their domains to me, i tell them they're responsible for renewing them (which i use as a selling point for why they should transfer them to me).<p>for any domains/certs that require manual renewal on my part, my billing system (plug: <a href="http://corduroysite.com/" rel="nofollow">http://corduroysite.com/</a>) is set to invoice the customers for these a month or two in advance because it's entered as a yearly recurring service. if they pay the invoice, i see it and do the renewal manually (or at least verify that the domain is set to auto-renew with opensrs). if they don't pay the invoice, the domain doesn't get renewed. this is actually beneficial because sometimes customers want to let some domains go, so they will contact me and tell me to let them expire before the auto-renew date comes up.<p>anyway, as for your product, your free package seems like it would be useful for your target market (web developers managing a few domains). however, anyone with more than 15 domains would probably have a billing system or domain reseller account that manages all of this for them. for a large company with hundreds of domains needing your more expensive packages, i can't really see them manually importing and deleting lists of domains as customers come and go, especially since there is no integration with their billing system.<p>my point being, the product may get a lot of free accounts but not many paid accounts. perhaps you should look into integration with established billing/invoicing systems?