A contractor tells the client the job will be cost of materials and 35 per hour.
The contractor gets a discount for the materials. Since he is a constant customer.
Can he charge the client the price usual people pay or must he charge the price he actually paid for the material?
The price he should pay is the price that a contractor usually pays for such materials, as that was his cost for the materials. Since he is buying in bulk, he will get it cheaper then in a regular store, and that was his expense. If however the contractor gets an extra special discount, i.e. a relative of his gives it to him at half the cost then other contractors get it, then it is considered his present and his gain.