thought i did this one?

sales

sold for 16 keys

https://backpack.tf/profiles/76561198192602363#!/compare/1596240000/1596412800

buyout used to be 16

https://bot.tf/stats/listings/Y9GNZ3DD

untrace

https://backpack.tf/profiles/76561198150107313#!/compare/1580601600/1590019200

https://backpack.tf/profiles/76561198342161127#!/compare/1589932800/1590019200

untrace

https://backpack.tf/profiles/76561198043553200#!/compare/1583971200/1589500800

https://backpack.tf/profiles/76561198842201154#!/compare/1586563200/1589500800

untrace

https://backpack.tf/profiles/76561198021030718#!/compare/1533772800/1592179200

https://backpack.tf/profiles/76561198226026552#!/compare/1434178800/1596326400

untrace (sold with aussie ambassador for?)

https://backpack.tf/profiles/76561198269337198#!/compare/1595980800/1596067200

https://backpack.tf/profiles/76561198168909159#!/compare/1592092800/1596326400

untrace

https://backpack.tf/profiles/76561198988115547#!/compare/1595462400/1596067200

https://backpack.tf/profiles/76561198269337198#!/compare/1595721600/1595980800

sold for Spectral Swirl Taunt: Flippin' Awesome (18)

https://backpack.tf/profiles/76561198123389475#!/compare/1594684800/1595894400

https://backpack.tf/profiles/76561198988115547#!/compare/1594512000/1595462400

qs for 10 keys

https://backpack.tf/profiles/76561198337734785#!/compare/1593561600/1593648000

https://backpack.tf/profiles/76561198122425731#!/compare/1593475200/1593648000

untrace, to quickbuyer

https://backpack.tf/profiles/76561198410010726#!/compare/1590710400/1593561600

https://backpack.tf/profiles/76561198337734785#!/compare/1593475200/1593561600

untrace

https://backpack.tf/profiles/76561198305494036#!/compare/1592697600/1592784000

https://backpack.tf/profiles/76561198410010726#!/compare/1590710400/1593561600

bot.tf says 9 keys

https://bot.tf/stats/item?def=30106&q=5&ef=Disco%20Beat%20Down&craft=1&aus=0&ks=0&source=browser_script

https://gyazo.com/5c1e149f39a821fa725c40ad6d6b5ba1

untrace, to quickbuyer

https://backpack.tf/profiles/76561198869102869#!/compare/1592179200/1592784000

https://backpack.tf/profiles/76561198305494036#!/compare/1592697600/1592784000

bot.tf says 8.5~

https://bot.tf/stats/item?def=30106&q=5&ef=Disco%20Beat%20Down&craft=1&aus=0&ks=0&source=browser_script

https://gyazo.com/5c1e149f39a821fa725c40ad6d6b5ba1

other two exchanges are with a bot

https://backpack.tf/item/7956462250

mptf

https://marketplace.tf/items/tf2/30106;5;u62

nothing recent.

classifieds

https://gyazo.com/2848459b02fe63b0b3d484f36f92dfce

seller @ 17 for 17 days

buyers range from 8.4 to 8.5

mptf seller

https://marketplace.tf/items/tf2/30106;5;u62

https://gyazo.com/33e88a1149c0877b1a009ea0ff37704a

https://backpack.tf/item/2459135388

$28/1.9 = 15~

judging by history it's been there for awhile.

current mptf key price is 1.9 (could go up or down)

summary

1 @ 10

seller @ 15

1 @ 16

conclusion

8.5, 9, and 10 were all sold within a day. excluding as low outliers.

going with 15-16 here.