If you buy an owned vBulletin license (I believe they are selling them for $180), do you have to pay $180 year after year?
No you don't, you get free upgrades for the first year and then after that you can pay a small amount to get upgrades for a further year and so on. Your license however, lasts forever. If you didn't want to upgrade to the latest version you could go years without paying anything.
The last time I looked if you had payed the $30 fee each year you got the most recent version of the current series free. If there had been a laspe in your coverage so other rule applied. Instead of asking here why not just go to the jelsoft forum and read or ask for a definative answer
When your license expires you have 60 days to renew it at $40 USD, after 60 days of expiration, you have to pay $60. http://www.vbulletin.com/forum/showthread.php?t=268714
and it's worth every penny IMO it's when you have more then one that the updates start to hurt the old wallet..lol
No need if you owned the vB license. You only need to pay $60/yrs to obtain the latest update such as security fix from vB