Additionally, strong tax planning is essential, as your W2 income limits your ability to deduct passive losses.

I agree and additionally I'd recommend going down to the store and actually feeling them.

Also, most Umbrella Policies only pay out if your underlying policy pays out, and the underlying policy will do everything they can to find an exclusion or that you were negligent (which you probably were) in the cause of action to get out of paying the claim.

You don’t get to just expense the additional real expenses.

This is due to bonus depreciation which allows taxpayers to deduct 40% of qualifying property costs in the first year, in addition to regular depreciation for new construction and improvement.

That's an ADDITIONAL capitol investment made. 

These are professionals with additional training and a stricter code of ethics.

Even if you primarily rely on finding your own deals off market, it never hurts to have a reliable agent on your team as an additional lead source.

Buyers usually want to purchase on today’s value while sellers often want to use future potential of the property (“current rents are below market” or “room to build an additional property”, etc) to increase the purchase price or likelihood of a sale.

Making additional payments or taking a shorter term are just depositing more into that savings account (it's not like the property appreciates more by paying down the loan).