Rollerblading

Got a used pair for a really good price. The overall fit is very good and the bearings and wheels seem fine. The one obvious issue is the plastic ratchet straps above the laces will no longer close (the strap goes into the "ratchet" fine, but the "lever lock" won't stay closed).

I saw many replacement straps on Amazon and videos on YouTube. I have a fair amount of mechanical aptitude. Is this something I can handle myself or do I need to take it to a shop?

Beyond the strap, what else do need to look at for basic safety?

Let me know if I need to post pics.

Thanks so much

Joe