There are quite a few posts on scanning slides if you do a search For just 35mm then look at Plustek scanners (8200i SE) but I'd highly recommend that you get one with IR dust & scratch removal as it really helps cut down post processing time.

A 35mm film scanner won't cope with your bigger negatives & for those you'd need a flatbed scanner - Epson are often recommended (V550/600). I think you may struggle to get good results with your budget though. Of course you need the right connector for your Mac - it would be USB on a PC but I don't know what your Mac has. It seems Silverfast will run on MacOS as well: It's free to try but does cost to unlock the full version. Some scanners come with a version of Silverfast but if they don't then you can use Vuescan instead. I'm not too au fait with Mac OS but I think the key is not the scanner itself but the driving software. I'm obviously being a catastrophist, but some of the stuff is irreplaceable and I wouldn't feel happy sending it off to risk being lost/damaged. Yes, it was fairly tedious, but I've got a bit of time on my hands and there's only so much Netflix anyone can watch. It costs about £250-300 to have 1000 slides or negatives scanned, and honestly, I think its worth every penny to not have to do it yourself.I scanned in about a thousand slides at my Mum's a few years ago with a cheapo scanner and a laptop I had access to. The machines often cost around £5000 each. If you send it away for professionals to do it, the quality will be excellent as they use really expensive automatic scanning machines. It wasn't just the continual cleaning, loading and unloading of each slide, but faffing around with the software and saving each image and all that. Because it wasn't a particularly expensive scanner, the quality was 'ok-ish', but the process just took forever and I got fed up with it. I had a go at this a few years ago with a 35mm slide scanner borrowed from a friend.

Negative scanner for mac