Right now, a used 4GB GTX 970 is probably going to be your sweet spot if you can find a good deal, I’ve seem them at exactly the $200 pricepoint recently but sometimes as low at 180.
If not the GTX 960 is a decent choice more at the $130-$150 range.
I’d highly recommend considering those, with UE4 you want to go with the highest power card in your budget at all times, otherwise you will waste significant time in other areas probably eclipsing the cost savings.
Specifically 242.02$ ie. 191.01£ ie. 217.62€ for card (with VAT) and shipping.
Mainland EU.
How about RX 470? Still can’t find any info whether Max would work with it, man, looks like everyone is using Nvidia. But how about Unreal, does it have any issues with AMD cards?
I’ve never heard any complaints about AMD cards and UE4. Contrary, their previous generation is comparably fast when using the latest DX12 and Vulcan stuff. I got no idea about Max but your observation could just be because Nvidia is selling better, especially in the high end.
The RX 470 should be the best value for you, buying an unused card. In theory you should be able to get an RX 480 with your budget, but the limited supply has significantly increased it’s price.