Do I need a rear caliper tool or can I reuse shims on 2018 Civic?

[Adam.H]

I'm trying to save money by doing my own brake pad replacement on my 2018 Honda Civic for the first time, and while I've watched several tutorials and feel confident about the process, I'm stuck on a few practical details before I start. I've purchased the pads and have a basic socket set, but I'm unsure if I absolutely need a special piston compression tool for the rear calipers or if I can improvise, and I'm also confused about whether I need to replace the shims and hardware kit that came with the pads or if the existing ones are reusable. For DIYers who have done this job, what tools beyond the basics proved essential, and what's the best method for safely retracting the piston without causing damage? Also, how do you properly bed in the new pads after installation to avoid noise and ensure optimal performance?