So I would ask what you care the most about depending on the type of deals you do.I do think checking references and reviews is important as that's sometimes overlooked and some lenders are notorious for switch & baiting. 

Depends who you ask and how secure you feel about your income On the one hand being debt free is great, but leverage allows us to build our wealth quicker.RE investors are notorious for being cash poor, so I would avoid thatIf youre able to comfortably save 100k a year and have enough reserves, I think buying leveraged properties is the best way to scale.You could kill two birds with one stone theoreticallyThey say paying an extra month a year towards principal saves you 7 years on a 30 year fixed mortgageUsing that logic you can add 2+ months a year on your primary, and buy 1 property a year and keep enough reserves. 

The MLS price is always higher than the auction price because the auction price is first bid and there is a reserve in place.Online auctions are notorious for ghost bidding to get the price up which is why you see them come back online again and again.What do you think you are gaining by "using" Auction.com?

Those jurisdictions are notoriously aggressive in researching and pursuing offenders so you want to be extremely cautious.

3.zillow is used for browsing but notorious for being inaccurate with multifamily 4. tough to say without know more. 

We've gotten that advice from an old timer in the trades, but Chicago is notoriously know for lagging with issuing permits and performing inspections.  

The CBRE's of the world are notorious for overpricing their Broker opinions of value in my experience

BMO Harris is notorious for getting this wrong and reporting it as simply "revolving" credit.

I don't like them because a) they make lousy coffee  b) the pods are wasteful (I know you can buy reusable pods but imagine how often they get accidentally thrown away) c) they are notoriously difficult to keep clean. 

One perk with these companies is that they often extend the lease as construction timelines are notoriously difficult to estimate.