hI, I'm interested in the POS computer
Sure. It's in great condition
How much are you asking?
I would like to get $250 for the set
Do you  have the instructions that came with it?
You know I actually can't find the manual, but I'm sure instructions can be found online. I can, however, teach you how to use it if you come over
I was really hoping to spend a little less; and if you don't have the instructions, I may have to even buy a new manual; unfortunately, I cannot bring my Equipment to you, for show and tell - would you be able to take less?  Say, $100? 
Oh that's a little too low. I can maybe go down to $200. Would that be acceptable?
The add shows an asking price of $200, I almost felt ripped off when you asked for $250.  Can you meet in between at $150? 
How about $175 and I'll deliver it to you? You can test it all you want in your shop before you pay me.