Dealerships will offer better training. I worked for Toyota when I started and they sent me to Toyota classes. I learned Toyotas of course for the most part. But once you work and know the workings of a vehicle you are able to figure things out. Also say you went to Toyota you will learn hybrids also. Not sure but I don’t think independent will do that.

I have a 2011 Camry 52,350 miles. Drive around town majority of the time only. Bought it brand new.

As an auto tech, I would not recommend a transmission flush. Drain and refill and as the other person mentioned use factory fluid.

I was a dealer tech for 25 years. I got into warehouse maintenance job. Repairing machinery. Conveyer belts and such. Pay is less of course. But I have better healthcare, Monday-Friday schedule. Work in climate control warehouse. All holidays off. No overtime. And best no need to buy tools. If your good at diagnosing vehicles then this will come easy.