BobW2
Msot online bidding is an attempt to get "hungry" suppliers to bid lower and lower. It's a game with no winners. Not only they inexperienced as arunmarao says, they border on unethical. In my experience ( having bid a couple of jobs and watched others ) it's a no win game. The winning bidder is the one who makes the biggest error, is the most desperate, misinterprits the scope of the job or all of the above in various combinations. When the job is awarded its the start of an adversial relationship with many disagreements about about things like what's to be done, by who etc. The winner bidder and the owner spend a lot of time arguing about scope etc. IF you do one of these make sure you have a change order proceedure in place to capture every extra penny you can.
Bidding contest is usually done by people who want the best deal ( can you spell cheap) and their cheapness is reflected in the quality of their bid documents.
I have watched job bidding on line where I was sure of the scope and had a reasonable ideal of what the cost should be. You can watch the jobs go for a fraction of what it really takes to do them.
My advise is to bid once with a fair and reasonable price then turn off the computer. It's better to build your reputation on the quality of your work not the price.