Advice on Most Recent MPB OR MB with Optical?

[Gareth]

You're on the right track. 2012 13" MBP is probably the best option in terms of future compatibility. USB 3 and still current on the OS's. Personally, I wouldn't go older than that. And you'd be better off with the 128GB SSD for $609 than 16GB of RAM.

I'd rather go eBay than go for an older machine myself, then again, I pretty much always go eBay, so I'm comfortable with that decision.