Generally speaking, an employer cannot force you to purchase a certain type of car. However, there may be some exceptions to this rule. For example, if your job requires you to use a specific type of vehicle for safety or other reasons, your employer may be able to require you to purchase that type of vehicle. Additionally, if you are employed by a company that provides company cars, your employer may have the right to specify the type of car that you are provided.
It's important to note that these exceptions are not always clear-cut, and there may be other factors that come into play. If you have concerns about your employer requiring you to purchase a certain type of car, it's always best to consult with an employment lawyer to get legal advice tailored to your specific situation.