Die Meute der Erben (2001)

Arno Adelmann, a seemingly grumpy but likable retired builder, has his quiet life disrupted when he temporarily takes in his neighbor, Ina, a young pharmacist, and her daughter Caro, in his villa. However, Arno's scheming daughters and their spouses believe he's about to be taken advantage of by the young woman. They petition the court to have him declared legally incompetent. But the elderly gentleman is quite capable.