The actual chargable price for the product is the first price listed on the product page.
Regular price (if applicable) refers to the price that was originally set when the product was published. This will only show if the actual price for a product is lower than the regular price.
Lowest price (if applicable) refers to the lowest price for the product during the last 30 days prior to the current price was set. This will only show if the price for a product has been changed more than once during the last 30 days.
Note that the prices listed are the prices set by Heppo and do not take into account if a separate discount code has been used.