Usually on a straight staircase, a stair lift will be the least expensive option. They typically can be installed by the home owner and there are several do-it-yourself stair lift kits that are very affordable. These kits include a track that is attached to the stairs and runs lengthways along the stair case. A chair or small platform is then set up and down the track carrying a single occupant. Depending on the model, some are capable of supporting more than 500 pounds and spanning staircases that are over 30 feet long.

In many cases a stair lift can be installed less expensively than an elevator, but if you have a curved staircase, then you might be forced to use a curved stair lift, which is incredibly expensive. The major cost is incurred because the track will have to be custom built and not only does this cost a lot more, it also usually takes around two months. Generally a curved stair lift will cost 100 times more than a straight stair lift.

Due to the increased cost of a curved stair lift, an elevator becomes a much more attractive choice if you have a curved staircase. Cost wise the curved stair lift will be about the same as a residential elevator, but unlike a stair lift, elevators can be used by multiple people at once and also allow for people in wheelchairs to use them. A curved stair lift has little or no resale value, because the track is custom built to fit the staircase, so will only function with a staircase that is exactly the same as the one it was built for. Unlike the curved stair lift, an elevator will actually add value to the home, so when it comes time to sell the home, you will regain much, if not all, of the cost of the elevator.

Residential elevators can be installed into wood frame homes and do not require concrete shafts. They do require much more installation than a straight stair lift though and you will more than likely need to have a professional team come to install the lift. Many people choose to install the lift into a hallway closet and they can generally be retrofit into most homes.

If you have a straight staircase, a stair lift can be installed much quicker and for much less money than an elevator, but if your staircase is curved, you loose this advantage and it is almost always better to go with a residential elevator.