You could look online-

Ball joints for some models are replaceable- some are welded in. With the age, your not saving much doing bushings + ball joints at a shop versus installing new lower control arms. If the ball joint is replaceable-dealership will have them in-stock and last times I got them-much cheaper than buying aftermarket.

Benzs ride quality and handling depends a lot on rubber. Experience can judge bushing with a prybar + how centered they are on the shaft/bolt. But expect degredation starts around 7-8 years on rubber parts.
Alignment requires a spreader bar on the W124 chassis. It pushes the wheels apart like driving down the highway. You'll need to find a shop which has one or the dealership. Even with that, there is a huge range of "in spec" which don't handle or drive well. Spec range is large and it takes some experience with these cars to get them right... mine needs more toe-in.
Michael