More questions!

Just bought my 2018 wrx base. Thinking about upgrading the exhaust and getting a tune. Can professionals run a tune with out an access port? Or is that necessary ? I’m not necessarily looking for more power. I’d like the car to sound a bit better but really I’m looking for longevity and whatever I can do to make the car last as long as possible. Some say don’t even touch it and leave it stock. Appreciate any advice, as I’m new to the car world, thanks.