Proof below. Undervalued and 5 month-old price.

Clean only

Sales:

http://www.tf2outpost.com/trade/18088288

-b/o of 7 buds

-bought duped blizz ke: http://www.tf2outpost.com/trade/18085163

-lower than 5.5 buds, outlier looking at offers

http://www.tf2outpost.com/trade/16733631

-wanted 8-9 buds

-tree+6 keys bought scorching hermes (price was updated with this hat): http://www.tf2outpost.com/trade/15440016

-~6.3 buds

http://www.tf2outpost.com/trade/18296279

-b/o of 9 buds

-sold for 6 buds

http://www.tf2outpost.com/trade/17718693

-b/o of 11 buds

-sold for stormy tossle (outdated)+5 buds=~7.7 buds

http://www.tf2outpost.com/trade/18550624

-sold for dp tc+sweets=dafuq

http://puu.sh/7yMlM.png

-terror muffs+stuff=~12?

Current trades:

http://www.tf2outpost.com/trade/18211312

-b/o of 10 buds

-notable offers:

cloudy whoopee (outdated)+10 keys=6.5

stormy beak+searing tree (both outdated)+25 keys=6.4

6 buds

disco dappers+1 bud=6.2

pe spartan+pro sfrl=?

lantern sam (outdated)+10 keys=7.1

-on other trade:

c9 jefe=7.4

dp sam+3 buds+lime bills=6.7

http://www.tf2outpost.com/trade/18422354

-'quickselling' for 7 buds

-notable offers:

3 buds+39 keys=5 rejected

5 buds rejected

http://www.tf2outpost.com/trade/15185134

-wants 8 buds, old trade, seems to be very particular about what he wants

-recent notable offers:

misty hw=8.1

7 buds

miami scrap (outdated)=8.4, probably lower by now

7 buds+pink robro=7.1

disco pillar+blizz hallmark (outdated)=7.1

http://www.tf2outpost.com/trade/13915898

-wants 9-10 buds, almost half a year

-recent notable offers:

electro gibus=over 10

disco cannon=over 10

http://www.tf2outpost.com/trade/18394939

-notable offers from old trade:

burning mirror+3 buds=~6 (he would take if he accepted the 3 on mirror)

scorching bonk+lantern pe (both terribly outdated)=7.6

http://www.tf2outpost.com/trade/17994491

-wants 10 buds, 1 month

-notable offers:

6 buds

7 buds

disco ck=9.4 outlier and outdated price

http://www.tf2outpost.com/trade/18652525

-b/o of 10 buds

Sales: 5.5, 6, 6.3, 7.7, 12

Low end is clearly 6. It may be extremely easy to get offers at least 6 but people still seem to accept them. 8 is high end due to a sale close to 8 and 1 or 2 offers close to that. Probably not possible to get 8 buds pure but waiting a while gets you a few offers of 8 in (shitty) unusuals. Offers clearly range from 6-8.