Straight stairlifts are the most affordable option, but they work best for stairways that don’t have landings or curves. If your stairway isn’t straight, you’ll have to invest more in a stairlift that curves with your home’s structure. In some cases, you can buy two straight stairlifts instead of a curved one, but this will be expensive as well as inconvenient since the person using the lift will need to switch chairs when she or he reaches the landing.