Buying any Karambit for 85% of Steam Analyst Price
( most people buy for 80% ;} )
[H]: 84K
if you add any extra keys, you're blocked

TUTORIAL FOR NEW TRADERS
to check how much of your knife is "85%", go on csgo.steamanalyst.com, type in your knife in the top search bar, check how many keys your knife is worth, on Google, type in "85% of..." whatever number your's cost. If you get a decimal, round up or down accordingly.

example: Bayonet Tiger Tooth FN - 91 keys
85% of 91 is 77.3
so i'll buy it for 77 keys