A price book that does not have its own rate
Every flat rate book on the market ships with somebody else's hourly rate baked into every line. You open it, the numbers look about right, and you have no way of knowing whether they cover your truck payment, your general liability, your workers comp, or the four hours a week you spend quoting instead of working.
A System takes the rate out of the book and puts a full break-even calculator behind it instead. You fill that in once with your real overhead, your vehicles, your wages and your actual billable hours. It works out what an hour on the job costs you before you have made a dime. Every price in the book is then built from that number. Put your insurance up in January and the whole catalog moves the same day.
The part most contractors have never done
Most people in the trades have never worked out their break-even hourly cost. They know their wage, they know roughly what the truck costs, and the gap between those two things and the real number is where the money disappears. The calculator in here is the same one sold separately in the shop, except it is wired into the book instead of sitting beside it.
Twenty minutes of honest inputs and you will know the number under every price you quote for the rest of the year.
Then the quote builds itself
Pick a service on the Job Entry tab and the three prices fill themselves in. The Presentation tab turns those into a one-page proposal with Good, Better and Best on it and a line for the customer to sign. The Job Log keeps one row per quote so you can see what you sent and what closed. The Software Export tab has the whole catalog formatted for Housecall Pro, ServiceTitan and Jobber if you graduate to one of them later.
Watch what comes out the other end
The Presentation tab is the point of the whole file. This is what the customer ends up holding.
Which one to buy
If you run one trade, buy that trade's System at $199. It comes with that trade's code reference, the Customer Manager and the Job Profitability Tracker, which are $120 of tools on their own.
If you cross between trades, the All Trades System at $399 is one workbook with all four books in it running off a single calculator, so you fill the thing in once rather than four times. Each trade still bills at its own premium over your break even, because an electrician bills higher than a carpenter and the file should not pretend otherwise.