Hugeduck (quack quack) Welcome to the forum. I totally agree from what you have described and parts listed. The bike had a CCT failure. Hence the reason the head was removed, valves replaced, new head gasket etc etc. The previous owner is just lucky the valves did no make a hole in the piston. Otherwise the bill would be 3 times as much.
Stick around here and you can't go wrong, plenty of advice and guidance and members willing to help out.
The only other thing you need to look out for is the regulator rectifier. check the regulator rectifier to see if it's a finned version.
Some links regarding the Cam Chain Tensioners (CCT's)
CCT's can go at any time, it's a gamble!
You can either go for the stop mod
http://www.vtr1000.org/phpBB3/viewtopic ... 31&t=19416 Which is the Honda auto CCT's that are converted to a fail safe. So when it does fail, it don't send the valves crashing.
Or
You go for the full manual conversion, your options are here
http://www.vtr1000.org/phpBB3/viewtopic ... 16&t=22720
Then with regards to fitting View Topic View Topic
http://www.vtr1000.org/phpBB3/viewtopic.php?f=31&t=8326
Regulator rectifier you will find attached to the subframe just behind the tail panel on the right hand side near the battery.
(:-})