I just saw that you'd be going from 6.5; my quote would be much higher than what the "standard" upgrade would be (I'm pretty sure this is the same with UBBCentral) as an upgrade from 6.5 is actually a quite painful process that must be done in different steps (upgrade to the latest in the 6.5 series, import to 7.2, upgrade to latest 7 series) and may in fact have to be done off your server (closing forum, downloading database and preforming the upgrade on a local dedicated machine to not hit any server resource limits) as some hosts will time out during an import.