Is the property fully developed?

Hello everyone, we want to build next year and have already found our desired plot through a real estate agent. The building plot was described as "fully developed." At the new building plots of the municipality, the blind pipes are about 1m above the ground surrounded by a black plastic jacket. However, this is not the case with the desired plot. When inquiring with the real estate agent, he said the connections are "on" the property. On the property itself, there is definitely a manhole cover. Probably for wastewater, but what about electricity, water, and telecommunications—could all of this be in the manhole? My question now is, how can I check or have it checked whether the real estate agent is really telling the truth and the connections really lie on the property. Above all, how can I ever find the connections again on such a large plot? Are there special procedures for this? Maybe someone can give me tips so I can avoid unnecessary costs :) Best regards Speer

hello I would directly ask the responsible [Stadtwerke] or the municipality they have to know.