The apartment really is as good as it looks. It's very spacious and comfortable, and because the owners also stay there it's equipped with everything you need. We were in Brazil for only a week and chose the apartment in order to see a bit more of the country after doing the sights of Rio. It was perfect for this, as it's only a hour from the city by car and seems to be the first rural, coastal village after all the suburbs. We were really pleased with our choice of place to stay, and would very happily stay there again.
About the location, yes you have to drive up a steep lane in the village to get to the house at the top of the hill. Personally I didn't find it a problem, even with four of us in a small hire car. In fact I found the short reverse back out of their entrance gate harder!
Marc and Aga are excellent hosts. All my messages were answered very quickly, and it was very easy to make all the arrangements. Aga met us on arrival, explained everything about the house and gave us lots of good tips about the local area. They were very friendly and helped to make our stay a very happy one.