Working alone most of the time, I often struggle with moving sheet goods into my shop. Perhaps if our driveway were concrete or asphalt, but alas we have a stone driveway. A few years ago I purchased a product called "The Troll" which claims to allow you to easily move up to 300 lbs around a job site. I suppose the job site they were referring to were all comprised of hard surfaces.
My solution was to build my own version using some steel scrap from a local steel yard and a couple of Harbor Freight tires. While it is not an exact copy of the troll, it obviously bears a strong resemblance. My version not only holds the weight of the other, but has no trouble traversing rough terrain and soft soils.