There is a lot of that type of software out there. Just look in the trade magazines. All of it has a cost -have had quotes up to 8K+ for all the modules parts bells and whistles etc.
Suggest starting with something simple. Take some accounting classes and some classes to use the various windows programs. Then you will have an idea of how and what you want for a program.
Personally I use Quick Books pro for the accounting and payroll. I use a spreadsheet for estimates. Because I have not yet got the two programs set uup to work together the way I want them to data gets entered more than once. I gave up on the Craftsman electrical estimator program. It's cost always came out 35-50% above the market here and changing cost in it never seemed to stay changed.
You will have to watch what ever you use to be sure your costs and bills are correct. Until you are comfortable with your programs and know you are using them correctly, you will need to double check everything.
Good programs are a great help but the learning curve is long and somewhat high.
Good luck