We want to start investing in real estate to offset that income by one of us becoming a "real estate professional".

You'd be well served to enlist the help of a local RE professional that's really familiar with these.. nuances, so to speak.There are at least a few of them on this forum.

This is true but some markets just won't see that type of appreciation.

Whether they do or not is entirely up to the bank.As far as a loan to an LLC is concerned that is also true.  

Sometimes you can get a great price and great terms.The same is true with real estate, except you are less likely to get both a great price and great terms.So you need great terms.  

People invest online all the time without being registered, however, it is still true that if someone comes after you through the court, you have no recourse if you're not registered as a business. 

If you don't mind living a little outside of the city, Ferndale and Royal Oak are great places to look, especially for young professionals. 

It so true even today with everyone going digital.

Research and Education is the key, even when faced with overwhelming opinions by professionals.

If the offer is accepted I schedule a professional inspection to verify the condition and life expectancy  of all major components and appliances.