I've been enjoying my 8350i BB curve for Nextel (the one you see in the commercials). The only knock, other than having to have that damn BIS (blackberry internet service so you can use internet browsing without Wifi and email push) which is additional $40 to $50 a month is the lack of 3G support (iDEN network just isn't setup or capable of the speeds. It's like fast dialup right now).
I suggest downloading the google maps. It's pretty robust for what it is. I think it may be useful for you considering what you do for living; I assume you actually have to go see some houses.
Don't forget to check out
Crackberry.com. There's all kinds of information on blackberrys there.
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