Thanks for your question.
The law states that up until 6 months after the sale of the vehicle, it's up to the dealer to prove that the fault (ie. the inadequate roof seal) wasn't there when he sold it to the purchaser. This is called the "Reversed Burden of Proof".
I would take it back to the dealer and approach the situation in a constructive manner stating that you like the car and do not wish to refund, but would like this remedied by them (for no charge). If they difficult then state that you are aware of the above reversed burden of proof and that it is their duty to remedy. You may consider posturing an application for a full refund as a bluff to scare them in to repairing.
If they do not accept that there is a fault you should state to them that this will prompt you in to getting it examined by an independent mechanic and you will seek to claim the cost from them and are prepared to make an application at Court for the loss if necessary.
If this has been useful please kindly click accept so that I may be rewarded for my time. It will be gratefully received and you will be free to ask follow up questions.
DISCLAIMER: Answers from Experts on JustAnswer are not substitutes for the advice of an attorney. JustAnswer is a public forum and questions and responses are not private or confidential or protected by the attorney-client privilege. The Expert above is not your attorney, and the response above is not legal advice. You should not read this response to propose specific action or address specific circumstances, but only to give you a sense of general principles of law that might affect the situation you describe. Application of these general principles to particular circumstances must be done by a lawyer who has spoken with you in confidence, learned all relevant information, and explored various options. Before acting on these general principles, you should hire a lawyer licensed to practice law in the jurisdiction to which your question pertains.
The responses above are from individual Experts, not JustAnswer. The site and services are provided “as is”. To view the verified credential of an Expert, click on the “Verified” symbol in the Expert’s profile. This site is not for emergency questions which should be directed immediately by telephone or in-person to qualified professionals. Please carefully read the Terms of Service (last updated February 8, 2012).