Danger signs to be on the lookout for when buying a 3GS on Craigslist for unlocking?

[Granitel]

Q: If you were buying an iPhone 3GS off of Craigslist for an Xmas gift for your young child ... what would you be on the lookout for NOT to buy?

• Personally, based on my prior experience with the 3G, I'd prefer a non-jailbroken iPhone 3GS so I could start fresh
• But, what iOS would I NOT want to get (which may be hard to JB)?
• And, which bootloader/bootrom versions should I NOT buy?
• Is there anything else in an iPhone 3GS to be on the lookout for?

HISTORY:
Naively, over the summer, I bought an already-jailbroken iPhone 3G for one of my kids, and only recently did I find out it's vastly important exactly what bootloader is installed (as the one I have is not downgradable):
- Why won't the bootrom version show up in WinXP Device Mgr iPhone 3G 3.1.3 BB 06.15.00

... sell this phone on your local Craiglist or trade up to a 3GS with an older baseband so you can unlock without using the Ipad baseband. It is little hard to find a 3GS with the older baseband, but these are still available.

I also had to downgrade the iPhone that I bought, from 4.2.1 to 3.1.3 just to run certain applications (Cycorder, in particular):
- Why would Cycorder simply flash black & blank out on a jailbroken Ios4.x iPhone 3G?


In the end, if I knew then what I know now, I would have bought:
a) A virgin iPhone 3G with an old iOS on it (e.g., iOS 3.1.3 would have been ideal)
b) An iPhone with the 5.8 bootloader version
c) An iPhone with the native (not iPad) baseband installed

QUESTION:
Q: What would you consider danger signs to be on the lookout for when buying an iPhone 3GS on Craigslist for use on T-Mobile?

 

[eastercat]

I don't care about iOS for unlocks. The only thing that matters is the baseband.

 

[TheDude831]

I have a 3GS I would like to sell. It is tethered JB'in, but it also has iOS 5, so it may not have the baseband you want. I upgraded to 4S in October. If you're looking to buy one, hit me up.

I was ripped off once on craigslist with a phone. I was very young, and naive. Didn't realize 95% of people on craigslist are scammers.

 

[labman]

I don't care about iOS for unlocks. The only thing that matters is the baseband.

1+ go baseband is what matters most for unlocks.. have the person tell you the baseband check here http://jailbreak-me.info/ or http://www.iclarified.com/unlock/ to see if that baseband can be unlocked 3GS and up basebands can not be downgraded except a few 3gs with the old boot roms.

buying on Craigslist is risky but ebay can be too. I meet people at very public places. my favorite is the police station..

 

[nebo1ss]

I have a 3GS I would like to sell. It is tethered JB'in, but it also has iOS 5, so it may not have the baseband you want. I upgraded to 4S in October. If you're looking to buy one, hit me up.

I was ripped off once on craigslist with a phone. I was very young, and naive. Didn't realize 95% of people on craigslist are scammers.

Generalization like that is such BS. I bought and sold stuff on Craiglist for years and never had a single problem. There are always those that will try to scam but they are in a small minority.

 

[Granitel]

http://jailbreak-me.info or http://www.iclarified.com/unlock

Very nice utilities!

At first, I couldn't get either of the two utilities to work (on a secure Linux machine); but when I dropped down to an unsecure Windows machine, both links began to work for me.

Then, I couldn't get either of the two sites to provide any information whatsoever for the actual current configuration of my actual iPhone that I had bought jailbroken off of Craigslist & then downgraded when it hung up in restore mode (i.e., the current configuration is iPhone 3G, iOS 3.1.3, baseband ICE2-06.15.00, bootloader 05.09 [G2M3S2]).

Neither site can comprehend my actual iPhone configuration.

But, I would assume, a 'virgin' iPhone configuration would be comprehended.

So, given that new-to-me information, I can definitely use these two wonderful sites to test whether I can easily unlock a 'virgin' iPhone that I can find on Craigslist; they just won't work for already jailbroken iPhones.