While Clara's place might not be the most centric of options to stay in Vienna, it is a short walk away from the next underground station so it is very easy to get downtown. I would recommend visitors to download the WienMobil App and get a dayticket so you don't have to worry about buying tickets. Start by exploring Schloss Schönbrunn and it's gardens - it is only a couple of stops away!
I like how Clara's place felt pretty much like a Hotel room (but cheaper!) as it had everything you'd expect: comfy bed, small desk and WiFi (good for work or if you need to do some research for your sightseeing tour), and a bathroom fully equipped with towels, soap and a hair dryer. The room has a fridge and a microwave, so it is possible to keep some things for breakfast or prepare a fast microwave meal.
Don't forget to bring along some earplugs though! Just in case your neighbors aren't very considerate ;)