Petsmart Sales??

Tank prices vary across the country and across some states. Craig's list is great in some areas and not too useful in others. Play around with the same searches in different cities some time.

I live near Lansing Michigan. Recently, South East of me (Detroit metro area) people have been giving away 100 gallon tanks they can't sell. South West of me (Indiana) used 90s are $2 to $3 a gallon.
 
do the search on craigslist by clicking the "for sale". That will give you a better search. Next best would be in "general" but that should be all included in "for sale". In my area I scored 5 old metaframe (1,5, and 3 15s) tanks with misc hoods, lights, covers and some gravel for $25. Good luck!
 
I used CL for my tank, got 75gal and solid wood stand for $120 and he had a coralife 4x6700k light that new was $249 and sold it to me for $70. He was getting out of freshwater, setting up a reef tank. Just keep looking, you'll find something. I almost bought a 55 for $250, it came with a metal stand,heater,hob,python and some other things, not a bad deal either.
 
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