I found some old photo albums and slides (mostly dating back to '80) and I’m considering digitalizing some of them.
How would you proceed in my shoes?
I have a decent mirrorless camera (plus minimal editing skills) and an office scanner, but I’m open to buy extra equipment. I’m also open to sending the lot to some third party studio that specializes in the task, but if possible (and if it’s not much more costly) I would prefer to DYI and process the photos/slides as I review them.

Depending on where you’re located, there might be some local services that are relatively cheap. If I were you, and I had it in the budget, I’d go for this guy:
https://www.bhphotovideo.com/c/product/1083201-REG/epson_b11b224201_perfection_v850_pro_scanner.html
(looks like it’s sold out though)