Zimmerman is the one that mentioned the mailboxes first. After he disengaged the chase with Martin, the 911 dispatcher asked him if he wanted to meet with officers and Zimmerman said yes. The dispatcher asked him where he was going to be and that's when Zimmerman gave him directions to the mailboxes. Actually, he said a past the mailboxes, and that's where his truck is. The dispatcher then asked him what residence he's parked in front of and Zimmerman said he didn't know the address. The dispatcher asked him if he lived in the area, he responded yes, and asked him his apartment number. Zimmerman then said it was a home and started to give the address, stopping short of naming the street, worried that he didn't want to give that information out, probably over the phone.
There is hesitation throughout the call, which is normal for situations like this. I think your imagination is running wild here because there nothing to indicate that Zimmerman was being deceitful or otherwise calculating.
Actually, if you listen carefully, Zimmerman hesitates to give his full address because he "doesn't know where he is". Which then begs the question how could Zimmerman confront Martin when he admittedly doesn't know where he is?