I was going to recommend exactly that. Excellent suggestion!
Used laptops (on Kijiji are dirt cheap [make sure you pay cash, use fake name, and text app to get it], and public wifi is everywhere. (Doubt Starbucks turns off their wifi hotspot when they are closed.

)
Just don't get sloppy and use the burner laptop from your home wifi or from your cellphone's hotspot. Your home IP will identify you in a split second.
It is really easy to be invisible. Just super easy to be sloppy.