My best suggestion,

if you want to just be carpenter (non-fighter) type merchant, you need to get someone (or maybe another one of your characters) to mark runes for each caprentry shop in the various cities. That way you can recall/gate/sacred journey to each to sell your wares to the npcs. When they stop buying at one shop, go to the next repeat until you sell everything. Now this style of playing will not get you rich and it will not be fast, but you should be able to afford to buy your boards from the npcs as you train up your skill.