Tank prices are high here as well, at some point I would like a 125+ gallon tank, but its crazy the cost to set up it new, and some of the prices on Craigslist are not exactly cheap either.My LFS store is awful I agree. Many things are marked up well over 500%. Not to mention tax is 8% here.
And you right it would cost that much here for you setup. I agree you got a great deal as well
Edit: For reference a 125 gallon tank was on sale last year for $250 at it lowest price, which over half off...Just for the tank.
Just some examples on Craigslist right now a 60G set up for $600, a 29G set up for $200, 90G bowfront $2500. These are all full set ups, tank, stand, filter, lights, average price for a 55G is $200+ There are also good deals though, a few months ago I saw a 150G tank only for $0 (wish I could have gotten that one) one ad is for 8 tanks (5 x 40G breeder and 3 50G breeder) for $40, again tank only. I got a 29G set up for $75 last year and felt it was a good deal.
I think the OP got a good deal.