In answer to Brandon "how much to charge?" I don't really know as I am just getting into this myself, but it did not seem to onerous, depending on the quality of the "consultants" plans and specs. And no you don't have to be on a special 203k APPRAISERS list.
In answer to Lee Anns ?? about contacts, and as additional info about being a consultant for others, I will give you my understanding and post some links at the bottom, I think there are a number of contacts in these documents.
They have "special training" for the consultants that writes the specs etc. for the 203(k) rehab program. After completion and submiting an "application package" that includes specialized experience, education, licensing etc.. Then one is placed on the FHA 203(k) Consultant Roster. There are a number of approved education providers. Several will do it via home study IF your qualified, have GC or Architectural background etc. I have all these guys info if someone wants it. Some of these classes do tend to sound kinda lame.
An approved "appraiser" must only be on the FHA approved list, with no "other" designation. I think the feeling is the appraiser is only suppose to engage if they are competent. (no comment from me here.) The appraiser cannot be the Consultant!! and vias versa. I geuss that makes sense.
I don't feel like the goal is to "overimprove" the property. The goal is to upgrade outdated housing stock, although you are correct they will do loan amounts up to 110%, but there are additional guidelines if the loan goes to that limit.
I am NO expert, however I was asked to get involved with this as I have a close friend that is going to be doing both 203(k) and Conventional rehab lending for Wells Fargo in my area. As I have 15 years experience as a GC they asked me to look into it. I literally have a ream or two of paper on it (much of which is Wells Fargo BS) I have posted several links below. I obviously had visions of getting TWO fees, one as the consultant and one as the appraiser, but those dreams have been dashed.
However my understanding is that you can charge $75 -$100 for draw inspections as work is billed and for the final inspection, and that EITHER the consultant or the appraiser can do that. Here are some links,
http://www.HUD.gov/progdesc/203k--df.cfm
http://www.HUD.gov/offices/hsg/sfh/203k/203kmenu.cfm