B=Budget | EL = Expected Lifetime | y=years
Smartphone: B=400-500$ | EL=3.5-5y
Laptop: B=700-900$ | EL=5-7y
Desktop: B=1500-2300$ | EL=10-13y
NC headphones: B=200-250$ | EL=1-2y
Note: I live in Denmark so prices might be a bit higher here. Also, people here are super greedy when selling their used stuff (especially digital devices) so I don’t buy second hand in general. The only exception is high quality wood/metal based furniture. My 2x1m height-adjustable desk was, like, 75$