Doing your own work would be more tax efficient. Your labor provides value in a way which is taxed as a capital gain and not income.
Another important quality in a flipper is not having unrealistic expectations. A tv flipper like Jeff Lewis wants to net a million or more a year, dealing in houses that sell for several millions. A flipper who wants to make a living can be content with several houses in the $150K-250K market and clear $60K to 100K a year, depending on the size of his or her family.