$169, I believe, for the full band kit.
If I wanted to add in cost of other instruments for RB2, it would be $60 + another $80 or so for the RB2 pro drums + $69 for the Fender Bass + $70 for GH3 with the wireless Les Paul. So not all at once, but overall: $279.
I don't even want to calculate how much money I've spent on DLC.
And I'd do it all over again in a heartbeat. Years of enjoyment.
Do multiple versions of the same game count? Ive bought about 7 versions of street fighter alpha 3 across different platforms.
I even made a thread about it years ago and the first reply told me i was sick and needed professional help.
Halo:Reach
$150 For the Legendary Edition at launch
$35 for all the DLC
$60 for a new standard copy later
$60 for a Games On Demand Version
$30 for another copy a year after launch.
$335.