Do you need a price for budgeting purposes, or are you going to be making a purchase shortly? Don’t assume everyone needs a full blown proposal. Many times a buyer is just looking for an approximate cost to continue research on buying the product or service you sell. They don’t even know if a purchase will be made, so why spend the energy and time doing a full proposal? You should have enough experience to ballpark a number for them based on minimal information. Give them a range, for example; “based on the information you’ve given me, I estimate the price will be in the range of $10-$12,000.
“May I ask who else is offering proposals?”
You may well find out that others bidding are a) not qualified, b) have a history of always be the low price bidder and you have no chance of winning, c) really strong, qualified and honorable competition and you better be prepared, or c) new to the market and you need to do some research. Wouldn’t it be helpful to know this information before you put your proposal together?
“Can you tell me the criteria that will be used to determine who the successful bidder will be?”
This one is really important. If the response is price alone, that will be a determining factor in how you prepare your quote. If lead time is primary that also changes how you respond. If it is multiple criteria you can ask the follow up question “is there a primary determining factor?” A few well worded and positioned questions can make the difference between winning and losing business.