Alliance server, i seem to be able to put prices far far lower then i use to be able to put my stock out for sale?

Ya, same here.
Last time I can put at $350, now I think around $250.

you can sell goods at 3x your PM price - if this is for food, the latest changeset dropped food prices on your pm from $360 to $100, so the max (if you do not have mil tech) is $300.

It would be nice if developers can improve the msg into more informative msg like:

PRICE_ABOVE_MAX $250
PRICE_ABOVE_MAX $350

It's better than having us players to keep on guessing and trying what should be the max price. =x

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