Although we have a large plot of land (1,700 sqm), we had a relatively small building window (9X13), so a basement (partial basement) was important to us. We have indeed partially developed it for living (underfloor heating, 2.50m height, plastered, tiled and vinyl floors, large basement windows, guest shower bathroom). However, we also had 11 meters of sandy soil (without groundwater up to 11 meters). With high groundwater, I would forgo it.