Permanent Residence in Austria

Good afternoon,

My wife and I would like to apply for permanent residency in Austria. I am a U.S. citizen and she is a Canadian citizen. We have already taken a German A1 course and are planning on taking the exam soon. This is our first time applying, so we're not really sure on the best way to apply. We're thinking of applying as self-employed workers, but we would not be starting a business in Austria. Our income would come from consulting work outside of Austria and building Internet websites. On the Austrian migration website for self-employed workers, it seems as if we need to start a business in Austria that employs Austrian workers.

We had a few questions about this:

Can we still apply for permanent residency as self-employed workers even though we are not starting a business in Austria?
If so, are we required to show that we have (as a married couple) more than 100,000 Euros in assets?
Is there a different or better way to apply for permanent residence in Austria?

I would appreciate any advice given as we are not really sure of the best way to apply.

Regards,