It depends on how good the domains are. If most of your domains are dsadadadasdas.com then expect $1 or lesser to be made. If all of them are reasonably good names you can make more than $50 a day but it depends on the quality. Sometimes a single good quality domain can make more than 1000 low quality ones.
1000 - 1500 domains would cost you $10,000 - $15,000 roughly speaking, you would get much better parking money if you used that money to buy only one generic domain name which gets type in traffic.
Anything from $0 to over $10 million. The question is too general. It all depends on the quality of the names.
I will say you'll be making around a million a year like everyone else who is regging names like crazy! yay free money.
best thing to do is: 1. create a website, maybe with blogger 2. start optimizing it for google 3. park the domain still... instead of parking them, i would create small websites and earn much more from adsense.
I agree, the money you will need to keep up with renewal fee's with all those domains will eat up a great deal of yor profit.
you better get going fast, each day you don't make money is another day you get closer to you high renewal fees...