The biggest money is not in reselling, but in developing new businesses or business models based on the names you've got.
But if you are satisfied with a 100% to 1,000% on the 8.99 you paid for the name, then reselling can prove okay. But remember to factor in your manhours in publicising/converting each sale.
The rest is all pure luck, so if you think you are lucky, then no logic or advise can or should apply