I suppose you don't have to know html, but you better know Dreamweaver in and out.
But its really better to know what your looking at since there are things Dreamweaver can't do and you'll have to edit code.
The main reason you just can't buy a site and have it work for you is that at some point, you'll have to edit/update/fix it which will require you to know how.
Speaking as a part-time webmaster with a full time day job, you'll see "part-time" in the adult biz equals a full time day job plus plenty of OT per day.
This is by far not an easy business to get into, but it sure is a hell of a lot of fun
