As stated below, times vary depending on all items noted. When asked by
department heads or project managers I usually respond with 40 hours.
Preliminary results for an early phase model can be completed in 4 to 8
hours. Appendix G with full documentation probably 60 hours plus. If you
are trying to match utility bills it could take even longer unless you
get lucky. The simpler the model the faster run time and budget time.

Hope this helps.

Robert Vogt