37k for electrical work is sporty! Respect!
For me, after signing the construction contract, the following were added: heat pump installed on the garage roof, additional sockets/switches/light outlets, cooling-capable room thermostats, nicer doors, plastered exterior walls in the basement, encased wastewater pipes in the basement, electric shutters, satellite system on the roof and matrix in the basement, more burglar-proof windows, nicer balcony railings, handrail at the front door and canopy above it, platform for the washing machine, extra shower with lifting system for the sauna, heavy-duty power line to the garage for the wallbox. Not on the list because I did all of it myself were all network, satellite, speaker and also some electrical cables incl. connections. Also not on the list because DIY was all the smart home stuff with smoke detectors, water sensors, etc. What was actually a massive deduction (!) for me were the bathrooms. Our standard was so good that we saved several thousand euros per bathroom, and that with four bathrooms.
The two by far biggest points that I didn’t have on my radar in this dimension were the garage (not just the garage itself but the specific construction measures necessary for me) and the outdoor facilities. This is not the classic checklist but especially the outdoor facilities are really often forgotten and then you ask a landscape gardener and then your face falls. Mine did too.