The worst thing you can possibly do in a deal is seem desperate to make it. That makes the other guy smell blood, and then you’re dead. The best thing you can do is deal from strength, and leverage is the biggest strength you can have. Leverage is having something the other guy wants. Or better yet, needs. Or best of all, simply can’t do without.

The situation at 100 Central Park South is a perfect illustration. Soon after I purchased the building, I did some research into the financial status of the tenants. What I discovered was fascinating but not surprising. There are three distinct groups. The first, who live in the largest apartments, overlooking the park, on the higher floors, are generally successful, wealthy, and in some cases quite prominent.

There is no substitute for due diligence. To this day, my father reads every lease our firm enters into. Before any building acquisition, every single lease must be reviewed. Yes, there are lawyers involved and that is technically their job, but he believes — and I do, too — that there is nothing like knowing the full story of a property, right down to the basic maintenance contracts.