Good riggers and machinery movers are worth their weight in gold. Others not so much. Moving a surface grinder can be a bit tricky, they are top heavy and there are not many places you can grab onto them from the top. Normally have to lift from the bottom. We moved a 2500 lb surface grinder just last week, and was able to lift from the top using straps, but it depends on the design of the grinder.
Your option is to rent a forklift, about 8000-10,000 lb, ($300?). Depending on the layout of the shop you may have to move the machine on skates to get it near a door where you can get to it with a forklift. This means moving the forklift for load & unload. If you have a tow vehicle that will handle it then you're in good shape, if not then you'll have to rely on the rental company to move the forklift.
If you can coordinate with the seller and move the grinder when they are bringing in their new equipment, then the riggers will already be on-site so no mobilization costs and you could probably get them to load out the grinder for a nominal fee. Then all you have to worry about is unloading when you get it to your shop.
Using a drop deck trailer is always a good idea, I have moved a lot of machinery on those. Getting a top heavy machine up and down the ramp can be a bit tricky. The ramp is shallow, but it is still a ramp. Ratchet pullers on front & back to control the machine is mandatory.
This picture shows the ramp a bit off of the floor due to the steep slope of the driveway, normally they will come down flush.
I hope this is helpful.