The stay was a great start to our trip!
Pros: Betty was amazingly communicative and had lots of helpful tips. Also, her apartment is in an incredible location for everything you want to see in Florence.
Cons: shower is quite small, and the bed and pillows were not the most comfortable. A bigger pitcher for water in the fridge (we kept filling it over and over!), thicker pillows, and some body gel in the shower would be excellent, inexpensive upgrades. For the less-able or those who pack excessively, note that the apartment is 4 floors up from the ground on a typical European staircase without an elevator. Not a problem for us with our carry-ons, but it was definitely a hill to climb after walking 10+ miles around the city all day.
Betty is an excellent host and the apartment is already a great value. If she makes the tweaks, it will become an incredible place.