This has been the highlight of my time in Portugal. My only complaint is that I didn't stay longer!
Not only are Rita and Vasco extremely responsive, but they go way above and beyond to help you out. Their place is a bit of a drive from Sintra (15 min) but Vasco offered to pick us up and even helped with our bags so we could explore Sintra first. (No small feat with our large bags, thanks!!) Colares is beautiful and we spent a lovely evening with a BBQ watching the sunset over the ocean. They perfectly and respectfully draw the line between giving you your space or having a good time together.
The loft itself is beautiful but don't stay here unless you are close with your second person. The house is Rita's grandparents' old home and both Rita and Vasco have renovated it themselves. The finishings are luxe and thoughtful, even offering homemade bath salts. The bed is comfortable, the AC functional and the TV has Netflix (though tbh the view outside is so beautiful you'll want to walk around or stay on the balcony). Also, their dog chilli is super sweet and friendly. I could not think of anything bad to say.