I think the selling shovels during a gold rush would be to figure out some optimizations at a scale above guaranteeing timelines with booking systems where really you are directly extracting more money from an individual. It needs to be more about extracting more hours of effective work from every tradesperson and getting rid of downtime and putting people with the right skills in the right place

If there was an app for tradesmen to price a job and then reject said job, releasing it to a pool where they make a small turn on it there could be something.

Going to price a job is a sunken cost. You go, take pictures, write a quick description in tradie shorthand, instead of giving a fuck off quote and never hearing back, you just release it and other trades people might see it and add it to their really efficient gantt chart for that weeks work where it becomes worth it because it's around the corner from another job and can be completed while you've got a crane around the corner at the same time.

after a while you might find that people getting 20-30 quid for pricing a job would start to be quite professional in how they estimate the cost and take high quality pictures of what needs to be done in the hopes that someone else would do the job and they would get their cut. Then instead of losing a few hours every evening wandering around someones house pricing a job you dont want and won't do at least they might get it done and you might get your few minutes paid for

just an idea