Depending on how much room you have inside the door and how you may feel about doing a little lifting, you can build a nice set in a couple of hours.
I used 5 step treated stringers and cedar deck boards and framing for the steps in the pictures. They fit inside the door of our 3400RL and weigh about 60#. I can get them in by myself but Lin usually helps out. For us it was cheaper, easier and something I could do on my own.