tangor - 7:28 am on Jan 19, 2012 (gmt 0)
New guidelines are same as the old guidelines: get estimates, a contract, partial pay to start, mid-term performance pay, then final on delivery. As for "validated code" you'll need to check that with each update submitted to make sure the product is worthy. You as the contractor have more to do with best final results than the workers producing.
I'd also remain open to any input the code team might submit that is NOT based on a static PSD layout... sometimes they have better ideas.