Know what one customer is worth
Work out what a new customer is worth to you over a year, not just on the first sale. That number sets how much you can afford to pay to win one, and without it nobody can tell you whether a campaign is working.
Test the whole path yourself
Click your own ad, read the page on your phone, fill in the form and wait for whatever happens next. If you lose patience anywhere along the way, so will the people you are paying to reach.
Make the page repeat the ad
If the ad talks about a free estimate, the page should open with the free estimate. When the page says something different, visitors assume they are in the wrong place and leave.
Check that tracking records a real result
Send a test enquiry and confirm it shows up in your ad account as a conversion. Campaigns optimise towards whatever is being counted, so counting the wrong thing teaches them the wrong lesson.
Start smaller than you planned
Spend a modest amount for two or three weeks, learn which audiences and messages respond, and then scale the parts that work. It is cheaper to learn on a small budget than on a large one.