The Storage shows are real. The auctions are regulated by the state of California and the seal on the lockers is not broken until auction time.
There are plenty of auctions that the guys on TV do not win, of course those are not shown on TV. There are also a lot of lockers they win that have nothing interesting in them and those are not shown.
Just look at how many auctions Dan Dotson is doing TODAY alone.
http://www.americanauctioneers.com/
Each "star" on the show is paid per episode, with it rumored that Barry making the most now that Dave is gone. The money Barry is spending really isnt his own. (Well I guess it is he could just keep it... but then that wouldn't be fun... and Barry is all about fun.)
Brandy and Jarrod do have a store and sell the items they buy from the lockers.
Darrell sells his stuff at a flea market. Not sure about the rest.
I am sure a lot of the in fighting between the stars is done for the cameras. Take a look at Lauras page at
http://www.paythelady.com/gallery.html and take a look at the lighting and gear they use, its not all guys with camcorders there is some major production going on here as well.
Any show today is for entertainment and Storage Wars is no different. But I do believe what they find is real... now the prices they value some of those things at I don't believe. I love it when Darell picks up a bowling ball and days "thats a $40 bill right there!"
Now the repo shows on TruTV... those are FAKE. The guy Lou actually produces that show as well as a bunch of others. The Repo show is supposed to be recreations of repos which have been souped up for TV. His show got popular in large Spanish Areas before it got picked up by TruTV.