I'm not trying to be rude, but PLEASE do no WASTE your hard earned money on that thing! I looked at the pics and can see that the "contact" wheels are "roller skate" wheels, things are not aligned as they should be, and the workmanship looks pretty shoddy to me. The type of tracking on that "machine" (tension spring tracking) simply doesn't work well for a belt grinder/sander. There's no doubt in my mind that you would constantly have belt tracking issues.
The type of controllers shown in the photos are a major pain in the butt!
My advice is to not walk away....but run away! IF you spend the money on that, your going to be kicking yourself, and looking for another grinder in short order. Save your money, and build it up until you can purchase a KMG or one of the other "top quality" grinders. If you do, you'll be happy from the start, won't have to be tinkering with it all the time, and you'll never have to purchase another grinder.
Many have heard me say this before, but it's worth repeating....the reason that the "top end" grinders cost as much as they do is because you are paying for the precision. That means that everything is square, true, and straight. All the wheels are top quality, lined up/centered perfectly, and the machine will operate smoothly right out of the box.....and with only minor care, will last a lifetime.