First of all... eveHQ may be the most useful eve-related software I have ever come across. Thanks for creating and maintaining it.
And the lacking option to use market data from a station instead of a whole region is the one thing I miss the most. I am using min/sell for my calculations as a producer. Right now I get the following values for Tritanium:
Maila VI - 1: 3.31 ISK
Jita IV - 4 : 3.79 ISK
Prism now uses the 3.31 as base price. So lets say I want to produce an Abaddon from a ME 40 BP. That's 13.383.780 Tritanium needed, which would equal the Blueprint calculator to show the value of the tritanium at about 6.4M isk lower than it actually would be buying from Jita sell orders. So I have to manually fix the prices for every single component by hand before I get a reliable cost calculation.
So if you find the time to add the option for station prices to EveHQ I would greatly appreciate it, it is in the API so it should be doable