Mike,
My wife is in the early stages. Your question is difficult because HD cases vary so much. I doubt if you will find a set of statistics, but I'll give you some ideas to start. Our medications cost approx. $120 per month (my cost). The insurance company probably pays that much. My wife is in the early stages. You can probably figure a neurologist visit every couple of months (approx. $175 per hour), psychiatrist visit every couple of months (same cost). Nursing home cost at $45-$60,000 per year. Cases typically run from 10-15 years, and my guess 3-5 yrs. in a nursing home.
Right now, the medicaitons are not working too well. My wife has no sick leave or vacation leave left. Her paycheck is probably half its usual amount (say $800 per months vs $1700 usual pay)--lost wages.
Feel free to ask questions.
Dave