Subdivision: …a tract of land surveyed and divided into lots for purposes of sale; especially: one with houses built on it ~ Merriam-Webster
In most planning regions, there is a maximum density (units per acre) governing the development of land. Without city water or sewer, Jefferson County has a density of 1 unit per 40,000 ft² or 1.089 units per acre. In a subdivision, each lot must have this minimum area. This spreads the building across the entire development.
Within a Planned Unit Development (PUD), the buildings can be grouped together as long as the density is met. This works by granting each unit a much smaller piece of land and holding the remaining as common or shared property. What this means to the buyer is that they are purchasing a much smaller area, sometimes only the building footprint and are getting a share in the whole.
Let’s say we have a PUD on 100 acres of hilly terrain with 108 cabins on it. All of these cabins will be located as far up the hills as we can get them (for the view of course). They will also be close together to reduce the amount of road per unit. If you were to buy into this PUD, you would purchase maybe 10 feet around the cabin, giving you a very small lot. You would also buy a 0.925% stake in the rest of the 100 acres, including the roads.
Not all subdivisions have Home Owner Associations (HOA) and the corresponding fees, but almost all PUD’s have both. When dealing with the private roads that are typically found in PUDs, someone has to maintain them. So, even if there are no common amenities, like a pool or club house, there still needs to be fees to deal with the upkeep of the roads.
There are benefits to both types of developments to both the developer and the land owner. There is easier construction and lower infrastructure costs in a PUD but a subdivision is typically easier to sell. When buying, there is less landscape maintenance in a PUD but subsequently, there is less personal space. One or the other, it is a personal decision for all.