I have found that many of my clients that are older than 60, tend to preffer a condominium particularly for the reason that many of the property responsabilites are taken care of by a management company, or at the very least the condominium board. I suggest that you look into the way the condo by laws are written to be sure you can adjust as needed to items such as wheel chair ramps, etc. Some associations may have verbage that prevents things from being built to the outside of the building if the property is not ADA compliant. Look for something with an elevator.
We are very close to the point where buying property may be more cost effective than renting. It wasn't long ago that this was not the case. There are many investment advantages with ownership if you can handle the long distance issues regarding property responsabilites, like up keep.
If for some reason your mother moves into assisted living, you have several choices with property ownership, one of them is renting out the property. Having said that, make sure that the by-laws (if you decide to go condo) allow that flexability. You can also sell the property. If you were renting, a lease can be difficult or costly to break, in such a circumstance.
The right answer for you has more to do with the answers to many questions about your mothers health, mobility, and the likelyhood of a change in the near future. From an investment stand point, you would certainly be creating equity and there is comfort in knowing that there is stability. Stability can be a big deal. Renters do not have the rights that they should when banks forclose. By renting, there is a risk of instability if the property owner falls on hard times and the bank forcloses. If that happens, you will be scrambling on short notice to find your mother another safe place to live. this has become an issue in the last 6 months and may continue for another 6 months to a year.
I hope this helps.