Inner tire wear on rears / Control arms??

[OZE53]

Hi Guys,

Mechanic recently told me i need new rear arms due to heavy inner wear on my rear tires. 19 Stocks. About $2300, this is on top of the $3200 i just paid for the service, so you can see my reluctance.

On closer inspection myself i noticed the wear only to be on the driver side rear not the passenger. My question / questions are do both rear arms need to be replaced together (left and right), should i get a second opinion or should i just try my luck and get a wheel alignment done? The tires are in reasonable shape other than the inner wear on the driver side

I have researched this but opinions seem divided, camber etc...... thanks in advance and thanks for all the other times you guys have bailed me out of trouble with the search of a few key words.

By the way, my car is a late 05' 3.0 sport with 42000 on the clock if that helps