The only real method that works will be based on the historical costs of your style of framing cut with your methods and tools.
Items to remember when bidding something you have not tried before: corners, larger timber sizes, degree of difficulty of joinery, experimental finishes, weather, site specific raising dificulties, new wood species (I use white pine as a benchmark and then apply a multiplier as needed), specialty tooling, complex metal work, did I say corners, unusual foot print and more, unusual height, secondary and tertiary pieces.
I also use a matrix of factors to crosscheck: Bd Ft, joint count, piece count, square foot.
Then there is always the old dart board.
AS the saying goes in the building industry: When you finally figure out your labor perfectly your price will be too high. Well presented high value work is easy to sell and quality sells itself. If you are bidding competetively against others and getting every bid your price is too low. If you are too busy the same may also be true.
Best of luck,
Curtis
