Should I trust this Amazon seller?

Some seller is giving a used iphone 5 unlocked for $300.It is a third party seller that listed in amazon and the account has just been launched. That seller is also selling an s4 and htc one for $300 as well.

If I buy this, can't the seller sell my mailing address to other people for more money and those people keep sending me spam mail everyday? They have a 30 day money back thing and that phone might break internally within those 30 days.

What's the worst thing that could happen if I buy this?

Added (1). Yesterday another seller had listed the same item for that price and their storefront had the exact same items as this new seller. Anything fishy here?

Added (2). Here is the seller profile: http://www.amazon.com/.../aag/main/

I thought amazon is safer than ebay or craigslist. How can buying this screw me over?

Added (3). BTW Amazon doesn't automatically deposit the money into the seller's bank. They deposit it after a couple weeks of sale. I heard the A-Z complaint can give me my money back if anything fishy happens.

My wireless network works for my iPhone, but not for me laptop?

My laptop says that it is connected to the Wi-Fi network (with full connectivity), but then when I try to open a webpage, it won't load. My internet works on my iPhone, so I know this isn't a problem with the router. I've already tried restarting the router, but this hasn't worked.

Apple AirTunes/AirPlay iTunes Mac

I have a powermac G5 connected via ethernet to my superhub router directly. My iPhone is connected to the superhub's Wi-Fi so they are both on the same network. Having read apple's website it states that both devices need to be on the same Wi-Fi NETWORK to be able to use airplay from my iphone to my mac. The powermac g5 doesn't have Wi-Fi capababilities by default so my question is:
Can i use airplay to stream songs to my powermac g5 when my iphone is on the wireless network but the mac is wired via ethernet or does it all have to be over Wi-Fi, which seems a bit stupid

Is 8GB a lot? I need your opinion?

On my android, I have 300+ songs. I have a 2GB sd card, and around 6GB combined for system and internal memory. I know that if you get an 8GB Iphone, you really have 6GB because of the apps already included in it. I take moderate amounts of pics but a lot of music. The reason I'm leaning towards 8GB is because the iphone 4 8GB is free at the moment.

How to set up black Iphone 3 or 3g?

I got a black iPhone 3. I'm not sure which one it is but it's the third one. I turn it on and it takes me through the simple process. First language, then Region, then it makes me connect to Wi-Fi so I'll try that and then it says "It may take a few minutes to activate your iPhone" and in the end it says "Your iPhone could not be activated because the activation server is temporarily unavailable. Try connecting your iPhone to activate it, or try again in a couple of minutes.".So I'll try to connect to through itunes on my laptop and after a while it'll say "We're sorry. We were unable to continue with your activation at this time. Please try again later, or contact customer support." I tried costumer support but I don't know my serial number. Please help?

Added (1). I only have the phone, no box and I'm not sure what carrier. Nor do I have the equipment to open her up

Got syrup in my iphone hearing part, and where the headphones plug in?

Yeah. I know. Weird, How did I do that? Well I work at ihop and did not have a case on my iphone and got syrup where I put my ear, and some in the hole where you plug in headphones or an aux cord… Both still work! It takes some pressure to plug headphones in, and when I'm on the phone I can't hear as well, its really dull. How can I fix this without drowning my phone in water? Or is it just ruined.