The only way you could be consistent with other companies is if you knew what they were using for a markup. Typically the percentage of markup is based upon the cost of the material. Something that costs $1.00 could have a markup of 100%. Something that costs $5,000.00 would have a lower markup.
Do you know what your overhead is ? What profit margin are you shooting for ? Knowing these two items will help you determined the percentage of markup to use.
Stop worrying about being overpriced or underpriced. There will ALWAYS be those who are cheaper than you and those who are more expensive than you. Figure out your price, send off your proposal and move on to the next job.
