My favorite is something like 162 or 176. It looks like provide welcome and opening for your clients, by the opened lid of the mailbox/house. I realy love the concept of the mailbox with a house shape. It's definitely a house, which means real estate, but it's also a mailbox in the same time by the opened front wall (that look like a litle arrow or pointer) which is pointed to the domain name, highlighting and accentuating it. So, I think it has multiple resonances in your business.
Cheers