Update killstreak item pricing to consider base item price

[FP jh34ghu43gu]

Killstreak items, impossible to price but the current averaging of scm sales is pretty alright at giving low end estimates. That's great and all for most items but when running into rarer items this price is often a terrible representation especially if scm sales are few and far between.

Obviously I'm using my own inventory as an example but I'm sure other items exist (probably other collector items). The example I have is professional killstreak collector scottish handshakes. SCM valuation places them at ~17 keys due to quicksells to buy orders from over a year ago. That prices them at a cool 43% of what a non-killstreak one is currently priced at which can lead to sharking for uninformed players that might acquired these items years ago before quitting and recently coming back to clean inventory (and obviously "undervalues" my inventory by a cool 726 keys  ) .

 

I think it'd be an easy fix to add a check where if the scm last sale is older than the base item's price and is less than the base item then the base item's price would be used instead. Maybe just a price comparison if the date of sales is not easily accessible with how it's setup and then revert back to the scm price if the base item price is over a year old.

[Urist]

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