You will not need anything else to do your frame except media. I used Black Beauty Coal Slag ($10 per 100lbs) on my frame. I blasted my frame myself (never again) with a normal blaster and painted it with this stuff.
www.nomorerust.com That's my frame on their homepage. Used a foam brush and it looks like powdercoat.
This attachment is the cheapest but won't take off the heavy duty rust like my frame had. I would fork out $250 and have it blasted professionally if yours is like mine was. If it just need cleaned up a little then use the northerntool pressure washer piece...