Hello Jaco 
My husband and I have been living in Lae about 5 years now. Lae City, in my opinion, is a great place to live.
Garbage removal is about K60 every 3 months although they are known to be inconsistent with rubbish collection. You will be issued different coloured stickers for your bin once you pay the fee.
Electricity depends on the electrical appliances you use, how often you wash, how often you use the air conditioning. To give you a rough estimate, it's just my husband and I in a 3 bedroom unit. We use aircondition every day but only in 2 major rooms. We wash every 2nd day and we never use the dishwasher provided. Everything else that we need electricity for is just our normal everyday kitchen appliance, the TV and charging our phones, laptop, etc and that amounts to K800! It can go up to K1000 if we have visitors and we turn on all the aircondition units in the house.
* Our aircondition units are old and are not serviced as often as they should be so they could even be a contributing factor to why the bill is so high.
Grocery shopping is close to K1800 - K2000 for a fully stocked fridge, pantry and other miscellaneous items. This is bulk shopping for an entire month! Drinking water is also included in this amount. We buy 19 litre bottles from 'Pure Water' which is the cheapest option for drinking water.
You could spend way less than what we do on groceries because you might stock your cupboard with different items, especially if your diet isn't a "Pacific Island" diet like ours 😂 No offence to my fellow Pacific Islanders ☺
Vegetables are cheap! I send my house meri on market runs every fortnight and for K50 I am able to stock my fridge with every kind of vegetable and tropical fruit you can think of! Again, it really depends on what you want so you can spend less or more.
Thats about all the information I could put together for you. I hope I was of some help.
Have a good day!