Unfortunately, I have worked for employers whose typical method of reducing costs for anything, including IT consultant services, is to proclaim how they can help the vendor with their contacts. Unfortunately, despite receiving high quality work at a cut-rate, these same employers were slow payers with short memories.

They would become incensed when the consultants requested payment of their deeply discounted fees - "what, don't they know how to manage their money well enough to cut us some slack considering what we can do for them?" - Then of course the consultant is written off as uncooperative and unworthy of a recommendation and I would be told not to request bids from them on new projects.

In short - get paid. Working for free or at a discounted rate does not increase a client's respect for you as a professional, it merely brands you as either a patsy or as a consultant who does not provide enough value to charge the full rate.