25% is a very low-ball number. Self employment tax: 7.5% Health insurance premium = 15% PTO + other benefits (life insurance, 401k, equipment, etc.) = 15% or

25% is a very low-ball number. Self employment tax: 7.5% Health insurance premium = 15% PTO + other benefits (life insurance, 401k, equipment, etc.) = 15% or more And there should be a premium on top of that for non-perm. The cost of contract renewal negotiations every year is non-zero.