There are three basic different mounting systems for residential basketball equipment.
Most home portable basketball goals use a water reservoir ballast system. These can be moved easily but the water must be drained or siphoned prior to movement and then re-filled. They are usually not very high quality. The water reservoir base tends to take up a lot of room.
Direct burial pole systems are very sturdy and have a very small foot print. They can not be removed easily. These systems are best for institutional applications. The pole must be installed exactly correct and level to obtain the proper height of the backboard and rim.
Semi-portable in-ground systems have the most advantages for home use. These systems utilize a pier mounting system that is very sturdy and also has a very small foot print. What makes them very appealing is that they are also easily removed and re-installed. To move a system simply remove four mounting nuts and lift the system off the pier. You then install a new pier at the new location and bolt the system back on. These systems make leveling the system very easy and accurate. This system comes with self leveling nuts under the pole plate that can be adjusted all ways until level.