Since you are a grandmother, what is your interest in stair-climbing? In 2 of our lodgings in 2022, a climb of 3-4 flights was required. This also involved our baggage - there was no elevator. If you have mobility issues, you need to make sure that the lodging works for your ability.
You need to get these accommodations ASAP. You are traveling in the high season, and pickings 2 months out may be limited.
In terms of travel insurance, we (71,74) have purchased insurance which includes medical evacuation back to the US. We are in good health. But if a serious injury occurred, costs to return in a medical evacuation can be substantial. As a grandmother, this is probably something to add to your plans.