Assuming you can manage with older hardware, it would be pretty hard to trace a random 7 year old laptop you bought used out of craigslist, right? You could even try to get one from someone that bought it used themselves.

the device in question still exists and should they have accuracy of variables that can identify machine in question.

You could just destroy it after 2 uses or whatever, old laptops go for pretty cheap.

One day you're in a coffee shop using the device in question simply browsing facebook......

Even if you don't destroy it, you obviously wouldn't be using it for anything personal at all. The only connection the laptop would have to you is the seller, who you obviously contacted using throwaway everything and ideally is not exactly a "reliable witness". Hell, even buying a bunch of shitty laptops over a year and waiting 6 months before using them would probably be enough to obscure your identity even if they reach one of the sellers.

I also assumed you wouldn't use a public wifi, rather someone's wifi to make the likelihood of getting caught by cameras smaller.

I mean, it's a pointless discussion really, but I can't imagine breaking into a house, using their computer there and leaving implies less risk than this.