Sorry, but this sounds like a bad idea all around.

1. Far more house than you can afford.

2. Far more house than they can afford. If you die or lose your job,
could they pay the mortgage?

3. An extra hour per day of commuting time for you. Plus the extra
time you will spend taking care of your parents. You might be far
better off just taking a second job.

4. Is living in a row house a problem because of *stairs*? Is that
why they want to move? Into a ranch style house all on one floor?

5. Neither you nor your parents has lived in a single family house?
Are they up to managing its continual upkeep? Yard work, exterior
repairs, raking and shoveling, taking garbage to the curb.

6. A single floor single family house ... would that be in a suburb?
How far from stores etc? Can your parents still drive a car? For
how much longer?

7. You will be the designated in-home care-giver. If that is your
choice, then make it so, but don't make it so complicated. Realize
that caregiving can be a 24 hours per day, 365 days per year *job*.

Una