Subject: Are there 2 separate routing charges

I want three single sided boards making, each 100x60mm. Therefore you will charge to separate the boards by routing. I also need a slot routing in each board, so the question is, is this included in the first routing charge or not ?
Can I place overlapping pads so that when they are drilled it forms the slot I require? or is this not allowed.
Please excuse my ignorance.
Ian