Cortez,
Did you choose an outside lender or theirs? If you were qualified on the base price then added options afterward, then Amy is right, you stepped out of the qualifying range. However, if you merely wanted to use another lender, then that is their selling tactic to get you to usetheir lender to keep all of the money "in-house" The National Association Of Mortgage Brokers is fighting this and I hope soon there will be a law that will prevent this intimidating practice. As of yet, it is not against the law for builders to do this, but if it is keeping you from buying a home with them when you have been approved for a loan then you can either look at another community to buy or buy there using their lender.
I'm a firecracker. If it were me they duped I would call the local media (T.V. and Newspaper) and tell them my story and expose this deplorable practice. But that is only what I would do.

How much in options did you put into the loan? If you were approved right around the base price and you put every single option imaginable into the loan, it might have put you into non-approval territory in the lender's eyes, just looking at raw numbers. I'm guessing this is the builder's lender. You never have to go with the builder's lender, unless there are certain promos or incentives like zero down and no closing costs that you don't want to lose if you went to an outside lender. If there are no incentives holding you back, then try to get approved elsewhere.

Mr. Smith,

The bigger question to ask is why the 30K decrease. Is it because the home did not appraise. If the home did not appaise with your 30K of upgrades then when you take the 30K out will it still appraise with the lesser standard items. The builder contract is sometimes biased towards the builder and may not have an appraisal contigency. But without reading your contract it would be tough to say. Do you have an agent representing you?

Cortez,

To answer your question, I would tell you that it would not be in your best interest to take legal action if you can anyhow. This is what I would do.

If it was the builders lender that approved you upfront, and they told you upfront that you were approved and later changed the approval to $30K less then I would try to see if you can get approved with an outside lender for the 30K higher. If that cannot be worked out, you could try to take legal action, but may not win. I would recommend you talk to a real estate attorney.

Hopefully you had your own representation. If so, consult with your agent. If not....

Bottom line is it will all depend on your contract. Different builder have different contracts.

Without reading the contract (and unless they are a attorney) no one here can tell you if you have any legal stance. Your agent should be able to give you some guidance however.

You should read your contract and consult with an attorney if you cannot fully understand the terms.