Pleasant Valley occupies the ground south of Reno where the developed valley starts thinning out toward Washoe Lake. It is unincorporated Washoe County, more rural in character than the subdivisions to the north, and the parcels tend to be larger with a wider spread of building eras than you find inside a master-planned community.
The single most consequential local factor for basement work here is wastewater. Where a property is on a septic system rather than a sewer connection, adding a bathroom is not only a question of whether the drain can reach it by gravity. It is also a question of whether the existing system has the capacity for another fixture group, and whether the county requires anything of you before that load is added. That is a question to settle early, because the answer occasionally changes the whole plan.
The mixed housing stock is the other thing to know. Older rural properties here sometimes have partial basements or cellars that were never intended as habitable space, with low headroom, rubble or block walls and no insulation. Newer custom building on the sloped ground more often has a proper lower level. The two need completely different conversations.
Being on the corridor also means the ground rises to the west toward the Sierra front, so parcels vary from flat to appreciably sloped over quite short distances.