$180 per month in the ball park ? Not around here, I wish. 110-140 around here unless it's a huge pool.
I decide how much based on what kind of car they drive, j/k lol. Start with your minimum, for us it's $75' for portables that are covered and basicly chem stops, inground spas only, $80', pools and pool spa combos $120' Then go up from there based on headache factors, try to not miss anything that will slow you down like, access, up or down stairs ?, shitty gates, multiple gates, keys needed, narrow passage ways, dogs, do you have to be there at a certain time or can you show up whenever, crap in your way you have to move or step over, equipment, pump basket access, skimmer access, raised bondbeam to climb up? extra tile to clean, can you walk around it ? landscaping, leaf problems obviously, good suction ?, extra long hose needed ? funky outdated equipment ?, vs pumps take more time and can be a blessing or a curse depending on the customer, salt system ? they're cool until they aren't. I'll take an older pool with a floater and tabs over a salt system anyday of the week, brand new smooth perfect plaster or a 20 year old pitted or scaled stained mess ? I ask why they're unhappy with their present guy, especially if the pool looks perfect. If it seems like an easy stop go with your minimum, if it seems like a headache charge enough that you'll look forward to going there, go through everything because once you tell them a price that's it.
I bid green ones time and material, freshly light minty green you might be able to shock, brush and clean the filter, long time green is normally drained. As for chemicals sounds like you got it. Whatever type chlorine you want to use, muratic acid to lower ph and soda ash, sodium bicarbonate to raise ph (spas with tabs mainly)
I started out working for a builder, when the pools were done they asked me how to take care of them and I usually got them on service. ( Funny side note: When I started my only transportation was an XL500, I would tell (sell) the customer a pole, net, brush, vac head and hose, a bucket of tabs and case of acid and liquid chlorine, then ride to the accounts on the XL and use all their stuff. Once a month or so I'd use the companies truck and reload the chems. Once I had about 15 accounts I bought a truck lol) After I quit working for the pool builder I worked as a night janitor at the high school. Get up at 6;30, clean pools until 1:30, then go be janitor from 2:30 to 11pm. get up and do it again. Once I was maxed out I quit the janitor job and went full time pool guy. Which was scary as fuck with a wife and 2 small kids but it worked out.
Insurance, I started with IPSSA because they had route coverage and have stayed with them even though I have employees doing the cleaning now. There are cheaper liability insurance companies but they don't have route coverage. IPSSA (Independent Pool and Spa Service association) has route coverage for self employed pool servicemen. (They don't cover pools cleaned by employees) It's designed for self employed pool service guys with no employees. The way it works is they have different chapters for a certain geographic region, there's usually 25-50 or so members per chapter, if you get injured, the other pool guys in your chapter each take on 2 or 3 of your pools and service them until your back on your feet again. So lets say you wad it up and break your arm, the other members cover your pools until you can work again. I used it twice before I had employees, once for a knee surgery and once for a hip replacement. It's a very cool feeling when you're all jacked up at home knowing that not only are your pools getting clean, you don't have any chemical expenses. If you don't care about route coverage look up ASAP or UPA.
I suggest getting a relationship with an experienced pool repair tech that you can sub out repairs to until you get good at it. With all the different heaters, pumps, automation systems etc. you need a guy who can get things fixed quickly if you don't have the time or knowledge. You'll get those calls where the heater starts and runs for 2 seconds then shuts off, could be the igniter, could be the ignition, could be the blower, could be the air switch, could be the exhaust temp sensor, could be a mouse in the intake, could be the thermistor, could be a dirty filter, could be the auto bypass if it's one of the new Jandy pile of shits. Don't even get me started on automation, sometimes the pump won't talk to the controller or they can't turn on the spa with their phone, the shits way more complicated than ever. If you can't figure something out you need a guy ("Your") repair tech to come out rather than having the customer wait. They don't like to wait lol.
Charge extra for specialty chemicals like conditioner, phosphate remover etc. change cracked baskets, old brittle skimmer lids, train them to be used to seeing extra charges on the bill so that becomes the norm.
Don't worry when Trip and Casey Carlisle underbid you, there's always someone cheaper. If a customer wants to grind you down on your price fuckem. That's the account you want your competition to have