Some Matzah bakeries use SINK TAP WATER for .מים שלנו
They will put into the chaburah matzos by the packing (pre-packed non your chabura "shitas ha'Rosh")
Some Chasidishe Matzah bakeries feel justified in overcharging for chaburah matzos to "non-Anash" (yeshivish oilum).
We have a minimum for using the ovens.
The bakery doesn't have enough sticks, so it takes longer, so you pay more, etc.
Make sure to establish a clear price, or go to another bakery.