Are you sure you want the boiler in your garage versus basement? I almost put mine in the garage thinking it would be dirty. I am very glad I didn't.
If you put it in the garage and have enough room, you can use a skid system. If you coal delivery truck has a lifting bed, you can hang the supersack bags from bungees off eye hooks on your garage door. They only have to hold the weight of the plastic supersack. The truck can chute the coal into the bags there and you can use a pallet jack to move the skids onto your auger box.
Make sure the auger box faces towards the front of your garage so you have room to line up the skid to it.
Click on blue link below for more info.EFM 520 Install with skid/bulk bags feed