bump

Because I had to answer few PMs regarding discounts, the best offer I can do is estimated price from bctalkaccountpricer (if you pay the escrow fee). But there are discounts possible if buying more than one account, -10% for two, -20% for three and -30% for all four. Updated first post accordingly.

With just fair to good post quality around 50-75% these accounts typically have, you have little chance to get to best paying signature campaigns, the competetion is too high.
 
So you eighter specialize for the low paying signature campaigns posting one or two linners all the time, or the higher paying signature campaigns by posting relevant posts with more effort and try avoiding the notorious 20+ pages spam threads as much as possible. Then you can have post quality above 90%, or like me around 99% so you wont find many one or two linners anymore.

There are discounts possible, especially if buying more than one account.

The prices are correct, bit above bctalkaccountpricer estimation, but it is hard to find similar accounts for sale with excellent quality posts allowing you to join any open signature campaign, including the best paying ones.