Making cell values correspond with Drop down List values

My title is rather confusing, but my question is quite simple. I have an invoice sheet with a drop down list in every cell in that row containing different rentals. When you pick a rental from the list I want its corresponding price (listed in the inventory sheet) to appear in the next column. I also was wondering if it was possible to start typing the name of a rental in the drop down list and have a list appear real time that shows the closest few matches and then one is able to pick from that list instead of choosing from an extensive list of rentals. The attached file should clear up any confusion.