This is the off-site rental car facility that serves the airport in Las Vegas. Almost all of the rental car companies are represented in this one facility, but you'll want to confirm that your rental car company is at this facility before you get on the shuttle bus.
When you leave the terminal, you'll find the rental car shuttles in a center island. The line may be ridiculously long, but the buses are big and can fit a lot of people and luggage and they come by pretty regularly. It will probably take you no more than 5-10 minutes to be on a bus on your way to the facility. The ride to the facility takes a few minutes. Once you get to the facility, look for the signage and follow the directions to your rental car company. Some of the rental car companies are more efficient than others, but that has nothing to do with this facility. Blame that on the rental car company.
Returning to this facility is pretty easy. Just be sure to use the address in Yelp and plug it into your GPS to make it easy to find. Signage to get to where you will drop off your car is easy to follow. Shuttle buses back to the airport are pretty efficient and fast, but do remember to give yourself time since the facility is several minutes from the airport.