I've never used Abebooks before and like most companies their reviews could be a bit hit and miss, although to be fair most of the experience comes from the seller. I contacted a couple of sellers, one of which didn't reply at all and the other replied virtually the same day. I bought from seller Better World Books (a US based company), they replied to all my emails and eased my concerns over condition. I'm from the UK and the book I ordered arrived well within the 7-14 day estimation and was in excellent condition, better than I hoped for, and at a crazily good price. I couldn't praise them enough to be honest.
If you're at all worried about buying from the site, I would advise contacting the seller of your chosen book first, even if it's just an email to check they have it in stock, you can gauge a lot from their communication.
Since I didn't have any problems, there wasn't any need to contact Abebooks so I can't speak of their customer service really, although I do find their site easy to use and fast. Having developed in-house systems myself I like that they develop their sites in-house so they should be fast to address any technical issues. I couldn't find anywhere to leave seller feedback on the site so if you're listening Abebooks, put it to the top of your todo list.
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