As far as contracting goes:
7-14 days after invoicing, paying out 66.5% to the subs is fair and reasonable.
30-37 days out after invoice 85%.
45 to 90 days they do not deserve to keep a dime.
Problem is these contracting companies seem to think they deserve all the profit while the guy that is actually doing the work (and his family) starves and loses money.
IMHO if these contracting companies cannot bankroll the contract they should not be contractors in the first place.