one of my concerns is taking on a job and then it taking me twice the time it should!
Quote for the job, not for the time.
Don't work for people where you "smell a rat". Walk.
Impress good people and word will spread like wildfire and you'll have more work than you can handle.
There are so many illiterate, dumb, rude, disrespectful, untrustworthy plumbers around that if you can sell
yourself, you'll never be short of work.
Saying you want to think about something, or find out more, will get you respect.
But it will take a couple of years.