The best age to buy a house is sixty.

Most non-villa housing standards and the overall quality of residents in the community tend to suddenly collapse at the fifteen-year mark—first and foremost due to the aging of the elevators. As the number of rental residents increases, bad neighbors become more common.
Although your property ownership lasts for seventy years and you pay $1 million, by the first fifteen years it has already suffered a loss of $500,000.
By the thirty-year mark, the pipes collapse, the infrastructure is in poor condition, and there is no management. At that point, a $1 million house is only worth $200,000.
If you buy at age sixty and live to ninety, you basically get to use this house’s “golden time” for retirement. When it reaches the ruined phase, you’re gone too—so you don’t need to worry about anything.