At the current stage, we focus almost exclusively on any measure that supports longevity, maintainability and repairability.

So we do not have any estimate. But if You really want to have a number: we have a budget of 4.000 €.

It’ based on the back-of-the-envelope calculation: according to statistics the average service life is between 8 – 12 years. Let’s say You’s buy a cheaper model one for 500 € and it lasts 12 years. So You’d need to buy  ~8 washing machines to reach the 100 years.
8 washing machines ✕ 500 € = 4.000 €.

If we manage to stay within the budget, it would be just a bit more expensive than a Huwa eDeluxe 70 (3.850 €, expected service life 20-23 years / 20.000 service hours, 25 years spare parts warranty).