Harv Eker in Secrets of the Millionaire Mind. 

My parents took a bite out of the American Dream as 1st generation immigrants with sweat and blood but they worked too hard unnecessarily because they lacked the knowledge of proper investing and building wealth.Biggerpockets and others are leading all kinds of people to investing which is an open secret; available to everyone but only practiced by a few.

Most of these guru programs get you in the door, provide you with some glitter and a few nuggets, then try to sell you the next level where you'll get the secret sauce that flips the coin.They're all the same.

I've dug through their website and I already know I'm going to have to keep this a secret from my wife... 

Followup is the secret. 

What is your secret to success? 

Bottom line: There is no free or paid guaranteed system to make money.Anyone who thinks they’re going to get “all of the real estate secrets” in a free seminar, 3 day weekend retreat, etc. just has horrible expectations.

Multifamily MillionsFinancing Secrets of a Millionaire Real Estate InvestorBuilding Your Own Guthrie CastleConfessions of a Real Estate EntrepreneurBig Money in Small ApartmentsSecrets of Power NegotiatingPrivate Money PartnersCreative Seller FinancingAdvanced Creative Seller FinancingThe Bankers CodeHow I turned $1000 into $5 Million in Real EstateThe Creature from Jekyll Island

Most of the time, they know that they are selling it under market; it's no secret.

Maybe you’ve got some secret knowledge that lets you go higher or lets you go in at ask.