I can recommend this appartment to all tourists wishing to visit Lisbon. It's in best location, 5 minutes from the subway station and 8 minutes from the Rossio train station (for trains to Sintra), near all restaurants and shops and though in a quiet street so you don't hear any noise at night. It's bright and sunny, true to pictures and very clean when you arrive.
Moreover, the appartment is very well equipped with everything you may need during your stay: well equipped kitchen, fast internet, TV, books, air conditionning for hot days and small, portable heaters for cold days, washing mashine & washing liquid, shampoo / shower gel, tea, coffee, hairdryer, etc. etc.
Initially, I was quite hesitant about staying in Bairro Alto as, not knowing Lisbon, I imagined climbing a lot of up and down but you shouldn't worry. I walked frequently from the appartment to Cais do Sodré (river level) and back and the road is going up very gently, with no stairs. It's also an easy walk with a suitcase. The same applies if you want to walk on Rua Garrett & Rua do Carmo to get to the shopping district - easy walk so your feet won't feel tired of discovering Lisbon on foot.
Cristina is a great host solving any issues very quickly and effectivly and the check-in process with Ana Paula (who takes care of check-in) was very easy. Easy check-out too.
I liked my stay a lot and would love to return there next time when I will be visiting the city again.