Without knowing your level of window knowledge, I'm going to assume it's entry level so I'll try to make this simple. Sorry to dumb down if you don't need it.
The sash are the frames that hold the glass. In a double-hung window they are usually the two moving parts (if it's working correctly). They are also what I'll be making for you to replace. The jamb is the larger frame that forms the box around the sash. I need to know the width and height of the inside surface of the jamb. When I make the sash I'll figure the "cutback" so they will fit into the jamb with the jamb-liners I provide.
It's usually hard to measure from the absolute bottom of the jamb because the stool covers the joint between the sill (the bottom of the jamb) and the lower sash. That's not a problem, particularly for merely pricing. For the height, measure from the top surface of the stool to the recess directly above the lower sash then add the thickness of the stool (7/8").
For width, just measure across the top of the lower sash from jamb side to jamb side. FYI, if you find variations of less than 1" the windows were likely manufactured the same size and dimensions have changed with age.
Again for pricing we don't have to be real accurate since the windows are priced in united inch bands (UI is width plus height). For example, windows up to 72 united inches are $xxx
Muntins do add up though. They are very labor intensive and I charge $YY per lite for windows with more than one piece of glass. So a 1/1 (one lite over one lite) is the price above. A 6/1 adds $YY x 6 to the price and a 6/6 adds $YY x 12.
Providing me a spreadsheet with columns for "location" (or some sort of ID), "width", "height" and "Muntin Qty" would be helpful.