Hi are you interested in this bike?
Hello, I am very interested, but I can't pay your full asking price.  If you are needing it gone ASAP and are willing to negotiate on the price please let me know.
yes definitely. we can work on the price, but I can't go too low. I am already giving it at a discounted price
Are there any additional perks or items that go with the bike you could include to make it worth my while?
I can give you the extra tires I had purchased them with the bike, and I never got to use them. They're brand new.l I can give that to you free :)
Are they tires only or is it an extra set of wheels with tires?
Tires onl;y
Hm.  Okay.  Well the bike is really nice and the tires will be helpful.  If I drive to you to pick it up with cash in hand would you do 650? 
that's too low. I can give it to you $900 nothing less than that
If you can drive to me I can do 800 but unless you have anything else to offer with it I simply cannot afford to pay your asking price of 900.
Well I have already given you the tires. I can't do more than that. Take it or leave it then. I am sorry I can't go lower than that. 
Then sorry I can't afford your bike.  Thank you though!