I bought feature phones there prior to my smart phone. They were used and cheap (flip phones) the flip phones tended to loose the screen picture when the ribbon cable got worn out from opening and closing them. Mine were fine I think I bought three of them. I doubt I would buy a smart phone from them as they are more sophisticated. When I upgraded to a smart phone as ATT dropped email on feature phones I sold two of the three spares I had to someone who did not need email there with no problems. BUT you are talking about small deals not s high priced smart phone...

Besides Amazon, try Craigslist. Ebay is known for scams, so if you find something way cheaper than other places don't trust it. And Sheila is right about the feedback percentage.
I had a terrible experience with a seller with a 100% feedback score and reported them to Ebay. I gave them the lowest possible rating but it only brought them down to 93.3%. To the average person this might look great but on Ebay there is a lack of trust. The only sellers that are trustworthy have thousands of 5 star scores repeatedly over years. This seller was able to look better at face value because they had 13 decent scores. Some scammers will build an Ebay profile that looks good to start scamming. And some sellers aren't scammers but are extremely difficult to deal with, such as the case with mine. You will have a much easier time dealing on Craigslist or Amazon.

Suggestions:
1- Do Search on opw reviews... that will tell you what other customers think.
2- Check ebay seller's feedback... Neutrals also count as negatives on feedback.
Anything under 99.5% I'd, personally, stay away from, especially when it comes to electronics of any kind. I have been burned on two, as of last month, sellers... both had over 99%, but under that 99.6%. As much as ebay Customer Service helps, you have to make sure refund requests are filed within the 30 days stated... but that's no guarantee the seller will refund anything.

Try Amazon.com