I've owned a business for 25 years where i have to guess/quote prices. If the materials cost is too much then ask for a partial payment upfront. Material costs. Labor. Misc costs (utilities, insurances, etc.). All are mandatory parts of your quote. Add in profit and then you do not care as to whether you get the job.
Let someone else suffer from underbidding. Or realize someone else has better technique/ equipment. But at least you know when you don't get the job.
Let someone else suffer from underbidding. Or realize someone else has better technique/ equipment. But at least you know when you don't get the job.