As a seller I say it depends on how you approach things. I don't mind when people want to deal, if it's friendly banter then we can usually come to an arrangement. But if they come across with the "I can get a better deal down the row" spiel then I send them on their way.
Better yet I will walk them to the competitor's booth and tell the competitor that they told me they could get a better deal with the competitor and so I was bringing them over for that deal. 9 times out of ten they were playing us both against each other.
I don't play that way. If you as a prospective customer want to establish a good conversation then we can do business and I am in a much better mood to come down in price. If you get aggressive then don't bother.
And please don't ever tell a vendor it will be cheaper on Sunday. It might but if you say that then most vendors would rather burn the product in front of you rather than sell it to you.
Remember that these are people who traveled a long distance and worked long hours to set up their booth and are working long hours standing there to present their products to you, treat them with some dignity and you will find them to be pretty hospitable.
That said competition is fierce so spend time doing your homework and scouting out what you want. Make sure you understand value vs. price. The lowest price isn't always the best value over time.
When you are reasonably sure about what you want then you can talk price. Have a reasonable offer in mind that you are definitely willing to pay and be a buyer. Don't be a tire kicker. Be upfront with the seller and tell them your bottom line and let them think about it. Be prepared to compromise.
Don't lowball. Especially with custom stuff. These cue makers put a lot of blood and sweat into getting cues ready for this show. It's a big part of their income. Of course they aren't a charity case but have some class when making an offer. If you do this with respect and manners you will make friends even if you don't get the price you want. Down the line in years to come that will pay off.
I have helped out former customers who brought their friends to me year after year. Always remember if you plan on going back to the show you want the vendors to welcome you not groan when they see you coming.
That's the best advice I can give you.
Be sure to stop by and see our line up of cases for your friend's new cue. I am sure you are going to want to have the best protection for it
