I wouldnt be too worried about obsolescence. I know in the past this caused a lot of problems, but these days the software makers put effort into making sure newer models of their softwares can read older models copies.

As far as companies going out of business. Sure that happens. You will get a warning from the company though, and the chance to save your own material. Besides if you print out copies of your notes and keep them locked up in your home that takes care of all those worries. This way you can create double redundancy. Save it behind 256 bit encryption on your laptop. Back the laptop hard drive up every week to a cd rom or other external drive or online service. Make sure to keep it encrypted. Print out a copy of each page of notes and keep them locked away. If you ever get in trouble restoring data from the computer you can always scan those pages. It cant be more safe, easily accessible and protected from harm than that.

As far as subletting, I have done it as a massage therapist. It worked fine for me. Find someone you are compatible with of course. You might not be able to decorate the place the way you want it.

I had a lot of freedom with my space. I could always call my corenters and ask if they were using the space during their time. If they werent they would usually let me book something during a different time. I did the same for them of course. It worked out.

good luck

Da Friendly Puter Tech