Question for all of you ATOT lawyers

[GoingUp]

Customer has a firm offer of item X for sale for $1000 from a merchant. Merchant also states that customer can get 10% off discount on item X. The 10% off statement is made orally though. Does the customer have a case against the merchant when the merchant refuses to hold himself to the agreement promised of selling good X for $900 or can the customer only buy good X for $1000?

Edit: State in question is Texas.

Basically I have a signed quote for $Z dollars and I was promised Y% off that price. They will no longer honor what I was promised.

 

AFAIK, oral agreements can hold up in court in many states as contracts. What state is this in? I won't be able to give you any advice, but the state would help a lawyer decide if you're in the right.

 

[GoingUp]

bump for edit