Re: What`s the time-frame professionals would consider reasonable for such a project?

Interviews can take days/months to complete, depending on the subject. If you have a large budget or very good planning, you could get your interviews say at a clip of two interviews per day, giving travel times and so on. I don't know what is "a lot", but if you interview 20 people that is 10 days. Assuming you take 5 more days to log all the stuff, you will then have to shoot all the "insert" and "illustration" material. If each person speaks for 2 minutes that is 60 minutes of illustration to shoot. At the usual 5-1 you need five-six hours of normal material (or three of very thightly planned shots) to have a choice what to cut where. There are few things as boring to watch as people talking. That's why there is the expression "talking head".

Depending on how you want to show Vienna, the shooting period can be as grueling as one week, as leisurly as one year or anything in between. It's up to you, your budget and your back. The time to cut all that... depends. For some a couple of weeks could be enough, for others a year is too little. It all depends on the treatment you accord the subject and the way you do it.

From the inverse point of view, in general terms, two months is practical for a decently professional piece of around 10-20 minutes from paper to finished, if you have a near-perfect schedule and frankly illimited edit time in a rig you know during those weeks.

I second Noah. If you want a director experienced in low budgets I don't eat that much and charge cheap ;)

.k.