Really handy list of stations that sell rares. https://forums.frontier.co.uk/attachment.php?attachmentid=9539&d=1421701372 You can do the rares run for a decent amount of cash but it can be a bit monotonous. Plus for the first half dozen stations you are just collecting so feels like a waste of time but if you persevere you can make lots of money and improve trade rank nicely. Plus I like rares.