I guess the whole point..... because I have seen both sides now, the person requesting the quote should tell the vendor 'just for budget' or 'needs to be real'
I know that most need to have a number to get the project approved but they also are the ones to know when the plant manager is blowing smoke and says "get me a quote" knowing very well that the cheap *&(*&)%)$#@! would never spend the money unless the quote came back and said FREE
General rule I use is if this a new customer then the first quote is always budgetary. Go with you gut and do not get to specific with the details. When/If they come back they should have a more defind scope and you should then start looking at doing a more accurate quote. If they say just requote again without more details, just hit them with the budgetary again.
Also on my budgetary I always go high, in other words I pad the heck out of it. When things get serious it is always easier on your end user to ask for less than more from the bean counters.
In a perfect world people alwys know exactly what they want and need, in reality that rarely happens.
One other thing I used to do alot, I would ask how much they expected to spend on this project. Most medium to large company's have to justify any project with a ROI so they know what thye can spend or expect to spend. If you come in over this then the project is almost always scrapped.
An example I can remeber was on injection mold machines I used to deal with at a previous employer. We knew that a .10 second decrease in cycle time was worth 20,000 to 30,000 anually. So when we did an ROI (our standard ROI was 18 months) that the job could not excede 30,000 to 45,000 depending on the product line per .10th cycle saved. If it was a bit over we may review and try to get "creative" with the numbers but in most cases we would scrap the project before it even stated.
Usually if I gave a bugetary number and heard nothing back I would call and ask, "did I come in to high for your budget". Usually I would then hear how much was the maxium they could spend. Or they would say the project was more than they expected. Your average plant/project engineer has no clue what it costs to build/modify controls. They generally as a rule underestimate it.
Where I am at now we hide part of the contol cost in the mech side because of the fact most end users underestimate the cost of controls.
My pet peeve is when a customer decides that we are to expensive on the controls so they are going to roll their own but want you to basically design it for them free and explain/fix whatever they screw up. This is generally the time I become "unavailable".
Not saying you do Genious, but alot of people forget that unless the project makes money for the end user there really is no point doing it.