I hate Chromebooks but some people seem to love them!
If I was in your position, I'd be looking at a refurbished 'business grade' laptop from a reputable seller on eBay, rather than on Amazon. This Lenovo Thinkpad X260, for example, would have cost you £1000 when it was new four years ago. It's now available for just a quarter of that price, from a seller with outstanding reviews:
https://www.ebay.co.uk/itm/Lenovo-Thinkpad-X260-Core-i5-6200U-2-30GHz-8GB-RAM-256GB-SSD-HDMI-12-5-Laptop/184549441215
Why did I select that model, and from that seller? Because I'm typing this on a Lenovo Thinkpad that I bought myself from the very same seller. It's an utterly superb machine, that could easily cope with the demands that your son would be making of it.