Approaching Apartment Complex Owner - face to face or letter?

[Guy Harper]

Researching apartment complexes, it's fairly easy to track down the owners.  Most recently I found an owner who is local and his place of business is fairly close to where I live.  Does anyone recommend blindly dropping by his work to approach him?  Leaving my name and number with his secretary or hopefully seeing him face to face.  Or do you think it would be better served to mail him a letter in hopes he gets it then follow up with a drop in?