My husband and I had a terrific stay. Our unit was pristine and stocked with every item that may you need and then some. It was in a great location for getting around SD and the neighborhood itself was lovely. The unit looked exactly as the pictures depict it . There were no surprises to be had. The outdoor area has individual seating areas and was very well lit in the evening. The owners are doing a great job of maintaining the property.
Four adults would be very tight. The bathroom is ensuite and I wouldn't have wanted anyone in the unit with me that I wasn't a very close family member. Teens or young children might be possible in the pull out couch, but a mobile toddler might be difficult as it is decorated "adult style".
We rented a car for our stay because we wanted to go further afield than San Diego proper for this visit. We found that once you figure out the tricky parking rules and restrictions you can park a car with success. You may have to park it a block or two from the unit but within an easy walk . In any case, car or none, the grocery stores deliver, and Uber is very available, not expensive and easy.
Kristen was available and responded quickly to any problems or requests we had and was totally friendly and gracious at all times.