You have three numbers off the internet and no way to tell them apart. You do not need to interrogate anyone. You need nine short answers, and how someone answers is worth as much as what they say.
1. Are you insured, and for how much?
Public liability is what pays if something gets damaged or someone gets hurt while a trade is working at your place. Ask for the amount, and ask for a certificate of currency if the job is a decent size. Anyone running a real business has one on their phone and can send it straight back. We carry $5 million.
For our part, what we actually hold and our workmanship warranty are both written down.

2. Does this job need a licensed contractor?
In NSW, residential building work over a threshold value requires a contractor licence from NSW Fair Trading, and electrical, plumbing and gasfitting require their own licences whatever the job is worth. Waterproofing is not in that group in NSW, but we refer it out anyway, because a wet area that fails is not worth the risk. Maintenance and repair work sits outside that. Ask where the job you are describing sits, and expect a straight answer either way. When a job belongs to a licensed trade, the right move is to send you to one.
A trade that tells you a job is not theirs to do has just told you something useful about every other job they said yes to.
3. Can I have that in writing?
Ask for a quote that itemises what is included, what is not, and what happens if something unexpected turns up. Verbal prices are how disputes start. Nobody is lying, the two of you just remember different conversations.
4. What is not included?
This is the most useful question on the list and almost nobody asks it. Tip fees, materials, painting after a repair, making good, scaffolding, a second visit. A quote that spells out the exclusions was written by someone who has been burnt before, which is exactly who you want on the job.
5. What warranty do you give, and on what?
Workmanship warranty covers the work, not the product. Materials carry their own manufacturer warranties. Ask for the period and ask what it actually covers, because "lifetime warranty" with no detail behind it is worth nothing. Ours is 5 years on new work and 3 years on repairs, and both cover our own workmanship.
Whatever a trade offers, it sits on top of your rights under the Australian Consumer Law, which cannot be excluded. Services have to be provided with due care and skill and be fit for purpose. A warranty is in addition to those rights, never instead of them.
6. When can you actually start, and how long will it take?
Not when can you come and look, when can you start. A trade that is genuinely busy will tell you a real date. One that promises tomorrow either has a gap or is about to double book you.
7. Is the person quoting the person turning up?
It matters more than people expect, particularly on small work, because the judgement calls get made on the day by whoever is standing there.
8. How do you handle it if you find something worse?
On repair work, opening something up sometimes reveals a bigger problem. The right answer is that the work stops, you get told, and a variation gets priced and agreed before anything else happens. The wrong answer is an invoice at the end that is more than the quote.
9. Can you send photos of similar work?
Not a portfolio, just two or three photos of the actual thing you are asking about. It is a fair ask and it takes thirty seconds to answer.
And one question for you
Send photos when you enquire. Nothing else speeds a quote up as much. One clear photo of the problem, one wider shot so it can be placed, and a sentence about what you want to happen. That gets you a real price instead of a site visit to work out what the job even is.



