Does anyone know how to dispute issues with tradies?

I had a pretty rotten deck in my old home which i am renting out to my sister, so i decided to get a builder to renovate.

I found a guy, ”Tom” (fake name) on service seeking website who gave a very reasonable etiquette and quote. I got a quote for 6.2k.

Tom calls me on the third day that the work would be completed by the end of the day, and was asking me to pay the remaining balance so that he can pay for materials and his team.

I paid it up like a fool before the completion of work. This was my first time hiring someone to do any renovation so I just listened to him like an idiot. And because i heard that there is shortage of tradies and how they are overworked, I thought I was doing a good deed by making the payment diligently.

Anyway, he did not complete the work that day and told me he was going to come back the next day to complete and to remove al the rubbish.

Then my sister found some issues with the work when she got home after work. The rotten part of the deck were not replaced, but had sister joists to support the rotten ones, some minor damage to weatherboard on the dwelling, and overall just incomplete job. The rubbish was left as is too.

I had orthopaedic surgery 2 weeks prior to the work commencement date, so there was no way I could possibly be present on site with them at the time. My sister is also a full time worker as well so she could not spare her presence.

I relayed the issues to Tom on messages and Tom gave me an empty promise that he will come back the next day.

he did not come back.

I sent him a formal email after 2 WEEKS of dragging, stating all the issues. Then he called me to promise that he will have everything fixed/completed in the following week.

Did it happen? NO

I still tried to be nice by being understanding of the shortage of labour and how he is aways fully booked etc. but nothing has been resolved. He kept giving me empty promises for a whole month.

Now, I talked to QBCC few days ago and explained the situation. Then I found out Tom is not even a licensed builder - I also had no idea that your builder has to be licensed. Which made me not bother checking the credential before agreeing to have him work on my house.

QBCC said it would take them 2-6 weeks to process the complaint and it will get referred to QCAT for illegally performing the renovation without a license and providing a defective work.

what is the likelihood of me winning this case if I went with QCAT? because i heard QCAT can take upto 6 months to give a court order or resolution.

I have zero idea about this industry and I feel ripped off. I have made so many rookie mistakes by trying to be nice, and this is what i am stuck with.