Teardowns, infill and the service you inherit
A rebuild on a sixty-year-old lot is not a blank sheet.
The water service running in from the street was sized for a bungalow with one bathroom, and the house going up has four bathrooms, two laundry rooms and a bar in the basement. The sewer lateral is the same age and often the same clay.
Both are worth dealing with while the lot is open and before the driveway and landscaping go back in. Same with the drain layout under the slab. Getting it wrong means breaking concrete twice, and the second time is always the expensive one.