So later today I will be doing some competetitive bidding on a rather large complex downtown. Nothing we can’t handle, problem is everyone and their brother is bidding on it, so I need to be “reasonable”… 
Not only your price but what you bring to the table will help sell your bid. You know what you will and won’t do the job for. Too low and you’ll hate it; too high and you’ll lose it. If the customer is only a price shopper then it’s a crap shoot IMO.
Two questions you need to ask yourself. What bid do I need to submit to complete this job and make a small profit for my company?
Second question is Why should they hire me? What do I bring to the table that makes me the company they want to hire for this job?
Answer the 2nd question first. When you submit your cover letter with the bid, if you have answered the 2nd question properly, they will call you in for a coversation and you can negotiate the first question to mutual satisfaction.
