not a lighting guy but I get this all the time with people who call me for a paver driveway, balk at the price and get the second guy to give them a price for black top.
I tell them word for word, "make sure its apples to apples, and spec out a, b, and c are included" they will call back and say x,y, and z but at least they keep it in mind.
I would hold out on the "not the lowest but the best speech" until the call back happens. Just sell yourself and your company. this is what matters most to the best type of customers. Of course you need to be in the market, but I say its a $10k driveway that will be here for 30/50 years, does $300 matter? I want you to have the best, not the cheapest