Raising speech craft through buying and selling

the-elder-scrolls-v-skyrim

So I found the khajiit caravan to be the most successful way to level my speech.
I'm at speech 83 now and wondering if items that are bartered have any effect on the amount of exp returned. If anyone has any idea please let me know.
Thank you.

Best Answer

The speech skill increase depends on the base value of the item traded or the difficulty of the bribe or persuasion. When selling items, it is not actually required to receive any gold, only that the transaction takes place. The skill increase only occurs once per transaction. In order to optimize leveling, expensive items in groups of 6 or more should be sold individually, rather than all at once.

source