@Charlottechelton In all honesty, £300 isn't quite enough to get you a good laptop for Sims 4. So if you don't like the options below, I'd suggest checking again around Black Friday or waiting until you're comfortable spending more like £400.
The best laptop I could find for £300 is this refurbished model. It should run Sims 4 on medium graphics settings, maybe medium-high if you're not going to install every expansion. It's in good condition, according to this site, with only cosmetic marks on it.
https://www.laptopsdirect.co.uk/refurbished-hp-pavilion-14-dv0598sa-core-i3-1115g4-8gb-256gb-14-inch...
If you don't want to buy used, your best bet is probably this laptop, which is slower than the one above but still has enough power to handle low-medium settings (all packs installed) and enough storage to accommodate all your Sims 4-related content:
https://www.currys.co.uk/products/asus-vivobook-x515-15.6-laptop-intel-core-i3-256-gb-ssd-silver-102...
Other than these, I don't see any options I'd be comfortable suggesting for Sims 4: the rest have processors and graphics chips that are too slow to handle more than low settings, or they don't have enough RAM or storage.
The other option is to buy from Ebay. If you're comfortable with that, let me know, and I'll take a look.
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I don't work for EA. I'm just trying to help fellow players with their games.
