I'm lucky that I use a greymarket app for Japanese TV that runs on mainstream consumer boxes.
If the vendor is insisting that you use their box and locks the application to that, that is suspicious; it clearly indicates they are not really serious about the service and really want that specific box in your home for some reason unrelated to the service. Huge red flag.
Everyone normal who wants to sell a service would much rather just sell you the service for $200, without that having to include any hardware; dealing hardware is a hassle. Except in one sense in that you can sell a validated total configuration that requires less support.