Helena's place has all that you need, it is close to a small shopping mall that has a big local store Tesco with great offers, and exchanging office with fair exchange rate 1€ ~24,5 or 25 CZK (called EXCHANGE). Parking is free around the building, internet connection is great. Trams 7 and 22 stop nearby and they will take you to almost all historical places for ~1€.