In reply to Robert Durran:
More like unrealistic.
I would say that you’d need to look at 1000 quids or more.
imho the two things you should look for are screen & prosessor. Unlike video, photo editing is pretty much only on the prosessor and not the GPU. So I’d guess that you’d like to have 8th or 10th gen i7 prosessor (or since you’re using windows?) you could also think about AMD.
Naturally SSD, but If the laptop has Thunderbolt3 (or USB 3.1) ports you can have your older pics on a separate external SSD (or big ass HDD). In which case you don’t need as much space. Not sure of this option suits you or no though.
The idea here is that you start using that LR you have, and keep the catalog on the internal drive, but the actual pics will be stored on the external drive. And as LR allows you to create so-called smart previews you can still edit them and see (just not export).
Besides, LR offers undestructive editing (also on JPEG) so you won’t detoriate the IQ If you edit them pics (but the con is the you will not see the changes via File Explorer as they are stored in the LR catalog).
I think the best bang for bucks might be a refurbished business laptop. They tend to be proper laptops and have at least reasonable screens. I’n now assuming that you plan on actually use it as a laptop. If it will only be stored on the home desk, then well laptops don’t really make any sense.