shipping cost reduce credits people will bid. Free shipping increases the bids. So it's like converting the amount you pay for shipping into credits you then use back on Listia. But can be double edge sword. Free shipping may not gain credits you deem worth the amount you pay in shipping, And shipping even at low cost may hinder bids and not get you credits worth item but at least you won't pay shipping if they pay.
On other sites like ebay shipping is understood as part of the game. Even so called free shipping is Almost always understood as part of the item cost.... But hear its snobby and people are more selective. So this site does Not work for certain items of value (leave that to ebay)
your title should state "Actual books" because if people just go by title them they may assume e books which technical people can find cheap or free..... Items with low shipping cost but decent fun value do better. Hope your action does well. Though 12.35 will reduce credits... may do better to see if will all fit in 5.85 flat rate box and set value of opening credits to bid at at least 500 and if asked for gin that's minimum set at 2000 and for this item and shipping cost is recommend take it.
How you require people to pay for shipping can change everything. People avoid send me cash as much can go wrong and Paypal gives proof of record. Money orders tack on extra to the original cost and people avoid. How you list shipping cost changes alot of things too.
Yes, sadly, if you want to earn credits, you'll have to offer free shipping. Even Media Mail shipping should only be about $4.33 (even counting a half pound for the box), and it's the same rate for books, no matter where in the USA you live.
Not trying to jam you up, just trying to help you get started!