Advice?

Hey everyone! I could use some advice. I brought my car into the dealership because I had the brake light come on. I was quoted like 4k worth of stuff to fix/ I only bought the car for 6k anyways. I also found out I’ve been putting the wrong gas in the car for about a year. I have the 3.6r and was putting in 87. Anyways, what are your thoughts on what they want to do. Is it worth it? Should I go someone that’s not the dealership? Appreciate your help! And yes, this was in December. My wife and I work at the same place and rarely use my car anyways but want it up and running for summer.

• not a car guy