Todd,   You do need to register your LLC in WI, and have a registered agent in WI as well, and file and pay taxes on income earned in WI, Check with a qualified CPA on this, but im about 90% sure this is the case

You can't eliminate the taxes, but you can delay them until retirement and earn compound interest on your tax money instead of letting the government earn on it.

It's just not required to get a peak under the hood nor to be the first to know about property.

A investor must insist that cash earns it's keep and therefor deducts a 10% return of the top of the rental income first to compensate for the fact that dead equity is too valuable to ignore. 

It is likely costing you 5% - 8% annually in lost income.You need to pull out all the equity and force it to earn it's keep in other investment properties.Cash should never be allow to wallow in a investment property.

A slip and fall of child or hi earning person where the insurance does not over the cost of the injury or possibly a death, they could come after you personally. a car or plane crashing into the property that would be in excess of the insurance that you purchase.

If you are interested, we could meet and discuss real estate and how you might be able to help with my real estate investing to earn some extra income.

The equity sitting in your property "earns" the interest rate on the mortgage, which is low but 100% guaranteed, as in you are certain to not pay interest on money you don't borrow ... refinancing that equity out and investing it in other projects "earns" the return on that project minus the mortgage rate, but there is more risk you take on.

Then, we get a comp for what it would cost move in condition, we make an offer, after deducting what it would take to sell it move in condition, we find a buyer who will fix it, we add our earnings %. 

Just be selective about what you put your hard earned money into.