Timeshare Scams and Fraud

Dear Madam Sir,
My husband and I reside in North America but own a timeshare located in Spain. We have made a number of attempts throughout the years to sell our timeshare. This company, namely Visions of the World with a location in the UK, advertised services that promised to find buyers in exchange for a fee. The stipulation was that upon sale of the timeshare, this fee would be reimbursed back to us. The contract indicates that you only have 7 days to cancel the agreement, which is not a sufficient amount of time to figure out where things stand or the reputation of the company. Following the agreement on a set sales price, the company sent me a contract that required my signature. Upon reviewing the contract, we realized that the company had conveniently changed the agreed sales price of our timeshare without our prior authorization or consent. Seeing as we had previously agreed on a significantly higher sales price, I immediately reached out to the Visions of the World contact (Charlotte Flint) to request an explanation. I was told that I had already signed the contract and there was not much demand for my timeshare, which is why the price was drastically reduced. I wrote to the Visions of the World representative several times to address our request to refund us for these so-called services. The company failed to provide us with any response. In addition, they never provided us with any proof of advertising services or updates. It is our belief that this company offers fraudulent, non-existent services and in the process makes a profit from trusting clients. This company also benefits from the distance between us. They owe us this fee, because we have repeatedly requested that services be terminated. Furthermore, we continue to be liable for maintenance fees, which means that the timeshare continues to remain unsold. In the past few weeks, we have researched this company online and encountered many reports and complaints from fellow timeshare owners who accuse this resale company as fraudulent, or in other words a sophisticated scam. They insist on keeping the fee, however they are not owed any fees for their non services. No matter how sophisticated the con artist, their contracts can never be considered valid or legally binding.