Pricing:

In a nutshell:

Pricing depends on what it is, where it is, when it is.
I offer value for money and fair warranty terms.

I've found that troublesome customers always find reasons to complain about the pricing and want to beat the price down somehow. I'm not interested in taking on such jobs.

Transparency in pricing (How rates are determined):

Employers usually pay their full time workers about $50/h (and it seems to me they offer full time work but then let them go when the work runs out, that's a whole other can of worms).

I made spreadsheets which calculate the charge out hourly rate when factoring in employee leave entitlements and core business licensing overhead costs.

Employee leave entitlements adds 10% to the base hourly rate.
Core business licensing overhead costs adds 2% to the base hourly rate.
Simple Workcover calculations are based on 18% of the base rate (Source, Page 13)
Base rate $50/h + Workcover equivalent $9/h + Casual loading $5/h + Contractor licensing obligations $1/h = $65/h
A wider range of services means more licensing obligations.
That's where I get the $70/h from if you have a good day's worth of work.
Travel costs work out to be about $0.80 - $1.20/Km, depending on travel efficiency.

A contractor isn't guaranteed 8 hours of work a day and therein lies the problem - the shortfall needs to be factored in to the hourly rate. Sometimes there's too many rainy days, which delay jobs that involve outdoor work.
At 50% billable hours, the hourly rate works out to be $130/h, hence why a short visit usually starts from $130 plus parts.
The more work you have in a day, the cheaper it gets.

Only certain jobs are charged by the hour.
High value services aren't charged by the hour but rather by the job. I have invested a lot of time and money in to bring you the best. I haven't yet recovered this money. There's also warranty responsibilities. Anyone can wire a house or install an air conditioner, but to master it and provide a service which pay for itself many times over, is another level.

Parts and warranty:

I do put a markup on parts. This also means there's no cost to you if they fail.
For electrical, where possible, I prefer the Voltex brand. They have good lab testing and an efficient supply chain, ensuring value for money. Their warranty also means you can ring them up even if I'm unable to get there in a timely manner, and you can still claim warranty through them.
You can bring your own parts. But if they fail or they're the wrong parts, this means extra labour costs you'll have to pay.

Discounts and flexible payment options:

Assessed on a case by case basis.
If money is genuinely a problem, let me know before getting a quote. I may be able to offer you the option to pay it off over time for a small additional cost (to cover inflation losses). The interest is indexed with inflation, because the money is worth less as time goes on (hence why grocery prices rise). Material prices rise because there is more money printed in to circulation chasing the same amount of goods.

Typical prices:

Prices based on typical house / domestic situations. Just so you have an idea of typical pricing so you can budget. Actual prices vary depending on installation requirements and circumstances. In many circumstances, the final total payable may be less than what's indicated here, especially if you combine jobs. Commercial prices may be higher due to additional parts and labour requirements. Prices indicated are not a quoted contract offer.
Niche services:
• Solar detection hot water switch: $250 - $800 depending on options.
• Fridge servicing / repairs: $500 (no cost if I can't fix it)
• Air conditioner servicing (bedroom): $700 (Add $100 for loungeroom)
• Air conditioner demand limiter (electronic timer based, for TOU tariffs or off grid): $350
• Air Conditioner gecko proofing (split or ducted): $400
The following air conditioners include gecko proofing, individual surge protection, and an extended warranty (7 years instead of 5):
• Bedroom air conditioner (2.5Kw):  $2000
• Bedroom air conditioner (3.5Kw): $2200
• Loungeroom air conditioner (7.1Kw): $3200
• Loungeroom air conditioner (8Kw): $3500
• Ducted air conditioner (Single phase, ~16Kw):  $13000
• Ducted air conditioner (3 phase, ~32Kw): $22000 
Brand offered is Hisense.
Other recommended brands include Rinnai J Series and Kaden.
Hisense is best value for money.
Rinnai J Series bedroom air conditioners are theoretically the most energy efficient but require larger gas pipes.
Kaden are just easy to use - insert the batteries in to the remote control, turn it on, and set the temperature. By default, fan speed and heat or cool settings are auto.
Common services:
• Small call out (Parts additional): $150
• Surge arrestor: $250 (Add $200 for 3 phase)
• Main switchboard upgrade circuit protection devices: $1500 (Add $500 for 3 phase boards)
• Relocate meter box: $5000
• Consumer mains cable upgrade: $1000
• Ceiling fans (Voltex DC, white 52" with light, 7 year warranty): $500 each 
Backup power:
• Generator backup power: $1500 - $4000 (BYO, depending on requirements and options)
• Add a battery to your house: $10000+
• Off grid (16KW solar, 10KW inverter, 32KWh usable battery, no generator): $25000