I take it they are going to surface the head and then R&I the valve guide seals without completely disassembling the head???

Once they have the springs off they should be able to "wiggle test" to check guide wear. If they are well worn, I'd suggest you have the head completely rebuilt including new guides. If the guides have over 100K miles, they are probably worn, and if you plan on driving the car at least another 50K miles, it might be a good idea to do a complete head overhaul, which may also require some new valve depending on stem wear. The exhaust valve stems will probably show more wear than the inlet valve stems.

Assuming they have a basic labor price for a head overhaul the add-ons would be for required parts.

Duke