Sorry ive been out of the 3ds scene for a while but arent all 3ds firmware hackable now? Also the trade in offer is $100 for the o3ds. Do you think i would be able to get more value selling it on craigslist?
$100 isn't bad at all, IMO, considered how it fairs with today's o2DS at $80 and n2DSXL at $150 (before tax), and that the last USA MSRP for the o3DS was $170.
See if Best Buy and Walmart will do you one better in a counter trade-in. Forget Target because their rates suck.
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As for selling it on Craiglist, your marketing skills will have to be put to use in up-selling that custom firmware. Throw in a couple of popular games if you can; I didn't say whether these will be carts or digital. Take great pictures of o3DS as cleaned up as possible with several poses in a neutral setting that has good lighting. You'll want different, slightly angled shots with homebrew apps in action.
You can try selling it at the sweet spot of $150 but don't give the option of best offer price because potential buyers will try to lowball you. While the technical minded 3DS user would rebuff your asking price as ridiculous, there are people out there willing to pay that if it means they don't have to mess with hacking a 3DS themselves. Just make sure yours is upgraded to the latest Luma3DS v9.1, GodMode9 v1.7.1, and boot9strap v1.3 on both the SD card and CTRNAND.
Other things to watch out for with Craigslist. Don't use your personal e-mail, phone number, and contact info in the sales page. I believe Google has free online phone service with Google Voice that will act as a "burner phone" or safety buffer. Also, your sale should be done at an agreed public space not too close to your home or too far (in case your buyer flakes out on you). Sit down places like Starbucks would do; your Walmart parking spaces is asking for your small item to be snatched and ran off with.
If you can, bring someone (preferably a male friend) along with you for the Buddy System, especially if you're a chick... Weirdo guys be all googly eyes. Also, if you drove, park your car at a different lot or wait until your buyer drives off before you do.
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While you potentially could get more money selling your 3DS on Craiglist, there is a bit of work you're putting in and precautionary steps you have to take. Also, if you live in an area that a small population, your chance in selling it would be smaller. Post an ad but put little effort in making it look nice.