Before deciding to seal the deal, it is important that you do a thorough research regarding the legitimacy of the site or the seller. Even renowned sites such as eBay will have shady sellers, and therefore it is important that you research well by reading the feedback of other buyers.
In case, you are dealing with a totally unknown or unidentifiable entity, then Google may be your best friend. Search extensively by typing the name of the company, address, and add words such as scams etc to gauge whether the site or business truly exists.
Leak out limited personal information
Some factors are in your control and make sure this holds true whenever performing an online activity. This will include handing out only necessary personal information. For instance, a credit card will serve the purpose for a particular transaction rather than your phone or social security number.
Lastly, it is important that you don’t just rush do get the deal done. Always review the information on hand, and get into the fine details. Your transaction must make common sense. If someone is contacting from a place which you have never heard of or is being too kind to you that will be a fair enough indication that something is indeed fishy.