Amazon has the Yaheetech 8-foot Sliding Barn Door Hardware Kit for $55 - $17 off with coupon 9WK9SOU2 = $38 with free shipping. Features 220-lb. door weight capacity, rubber cushion doorstops, anti-bounce.
Has good Amazon Reviews.
eBay has the WORX WX255L SD Semi-Automatic Power Screwdriver (Open Box) for $16 with free shipping. List price: $60. It includes a rapid reloadable cartridge that houses 6 common screw driving bits, making it easy to access and even easier to change.