50% of online transactions aborted

I read in the news that a new study says that half of all online purchases are abandoned instead of completed and they attribute that to slow-loading pages. From my personal experience, I think another significant contributing factor is the number of web-shopping sites that don’t give you the final purchase price until you are in the ‘check-out’ sequence!! If the price is too high or not what I expected, that’s when I bail. Others, too, I bet. What are your experiences?