How well do iPhone trade-in companies check your phone?

I'm looking to trade in my iPhone with a company like Gazelle or NextWorth. My phone is gently used but is missing the SIM card tray. I have replaced the tray, but it is not an official on from Apple, and is missing the ID number and what not. For those who have used these kinds of trade in services (including the in person ones), do you have any idea of how closely they inspect the phones? I'm hoping they won't notice that I don't have the original tray because then the $300 price tag gets dropped to $90. Definitely not a $90 phone! Thank you.

Added (1). Well, I'm not exactly expecting to get their top offer, but I certainly don't want the highest offer to start at $90.

You won't get anywhere near $300

You'd be better off putting it on eBay or Craigslist.

Try getting a quote at http://www.cashforiphones.com/ and see if the price they offer works for you.don't mind much if that's not the original tray they buy broken iPhones so you'll have a great deal with you phone.

Basically, site like this checks if the Powers on works fine, if your phone has a damaged or defective screen and if it has a broken battery.

If you have other devices you can consider checking its value at http://www.cashforsmartphones.com/ in case you want to trade them.