ok so the additional fields(Column names) are as above/below:
Which have already been selected and defined within the $Drop, $Drop_1 etc. variables chosen by the user.
So flow would be like so:
User selects each drop down box and enters desired options.
This then displays lowest/highest price (which we got working above with your help)
A button then displays that would give the user an option to display further details about the rows that are defined between lowest/higest price.
hope that makes sense..