"price on" and "price for"

Question

In Insider Secrets To Hydraulics book there are two sentences with price in it:

1) Befor the distributor can quote you a price on an equivalent pump, a sales engineer has to identify all the specifications of the existing unit, such as shaft, mounting, ports and displacement, and then cross-reference this information to find a suitable alternative.

2) Assuming the price for the 'Brand-Y' pump is cheaper than the price you were quoted for the 'Brand-X' unit and the two brands are similar in quality, you can use this as leverage to get a better deal from the 'Brand-X' distributor.

Can you explain to me why in 1) there is construction with preposition "on" and in 2) there is construction with preposition "for".

Answer 1

In this context and in idiomatic English "on" and "for" are interchangeable. There is little or no difference. By convention a quotation is often spoken of as "a price on" and when talking about the cost of an item it is "the price for" but there is no rule governing this. It would be quite acceptable to ask

"Would you please quote me the price for that job?"

Then again it is more conventional to ask for "a price on" but talk about "the price for".

There is also the perfectly acceptable "the / a price of..." which can be used in either context. "Quote the price of a pump" and "The price of a pump is ..."