My guess is that you have a Mexican timeshare.
All 5 are scams and all would work the same. They offer a ridiculous amount of money and promise no fees. However, they will make up a fee that will be due and then tell you that you will be reimbursed at closing. You send it and then they ask for another fee. This will repeat until you stop paying them and then they disappear.
To use another analogy, how often have you received unsolicited phone calls from someone wanting to buy your 2016 VW Jetta for $38,000? Only catch is they want you to pay them $1500 first.