Does it really cost that much?

Job description

I received a quote for a media wall building for £4000.00. The media wall is exactly like in this picture, just 4.5m long and 2.5m high. All materials included except fireplace and tv obviously. I had some relatives who had a media wall done 1 and half year ago, almost same size as i want, and they paid £2200 for it. Did the prices go up so badly, or they just try to rip me off? Need some opinions on this please. Thank you