Here is an example of what I charged for my customers a few years ago.

Chemical Service     14 step process - $55 per month + Stabilizer billed every 6 months @ $35 each

Visual check of pump & filter for leaks upon arrival
Check pressure gauge
Turn pump off
Set timer for correct time
Lubricate pump lid o-ring 
Clean out pump basket & reassemble
Turn pump on & ensure it primes
Test pool for free available chlorine & Ph (weekly) & calcium, alkalinity, stabilizer & water balance (monthly)
Add proper chemicals to sanitize & balance water
Clean out skimmer basket
Ensure automatic cleaner is working
Clean tiles (monthly)
Clean filter & lubricate orings (monthly)
Leave a note showing that we were there

Modified Service  16 step process  $69 per month  + $35 Stabilizer billed every 6 months @ $35 each
Brush walls where necessary
Skim pool surface

Full Service  17 step process  $80 per month  + $35 Stabilizer billed every 6 months @ $35 each
Vacuum pool