The room was very clean, spacious and nice! Renata is a very welcoming and friendly person, she and her daughter explained to me how to use public transportation and gave tips. It's not close to the centre, but there's a bus stop about 200 mts from the house.
TIP (not related to Renata's place): don't go to a minimarket called "twenty 4 seven" it's near the clothing store "The New Yorker" at the beginning Wenceslas square, on Na Můstku street.
Some items don't have a price tag and they charged me 3x more. Sadly, I was not very aware how much money I was paying. BTW, they didn't gave any ticket.