Bungalow is the correct description here- it's a housing unit in the back yard of the main house, the garden is in renovation at the time of our visit (Sep 13) so the picture of the yard is not relevant (we where told of it in the same day of arrival), the unit itself is a small and long wooden (thin wood or plaster).
we did liked the TV and the kitchen that was well equip for our use, the double bed was good as well the pullout sofa bed was less comfortable but OK.
there is a AC in the unit, but it was very loud and we couldn't sleep with it - we did w/o it (at night) although the weather was quite hot when we were there - we did fine with the vent on the ceiling .
Heather did turned the AC on before we arrived so it was nice and cool when we got there (~noon).
the best way to the unit is round back, from the main house it was (almost) not accessible - but it could be since they are renovating the yard at the moment.
the unit itself need some maintenance, the Tap (both at the kitchen and shower) tend to disconnect, and the curtain on the windows is not very good (they are folding plastic or metal type), and the one on the window AC doesn't close the entire window - so we had some light in the morning (if you are sensitive)
communication with Heather and Mike was great, and we got what we needed right away.
the neighborhood is not the best, as far as we show, I didn't feel fully secured leaving my laptop there (I did eventually), it is located not far from down town San Diego and Balboa park.
in general if you need a place to stay and you are not too fussy about small staff and the price is right for you - go for it.