No this probably has a boatload of mechanical problems for that price.
My sister's E39 had so many problems. Had a mechanic that specializes in Bimmer's work on it for like 2-3 weeks.
Window aculator failure, window seals kept cracking, A/C issues, odometer wouldn't work, etc
Don't get me wrong, E39's are lovely cars, in fact my favorite 5. But they're just prone to countless problems.
Better off buying a Civic or any other reliable car for your brother. The fact that you're buying a car for your brother is great though.
I would be so happy if my brother bought me a car.