Joanna's place is a great find and we would highly recommend it.
My wife and I stayed with our four month old son, and it had everything we needed (we took our own travel cot).
We arrived after the long flight from the UK on a sunday evening, and were grateful that Joanna came to meet us in person (although she had given us self check-in instructions so did not need to). She was so friendly and helpful, explaining everything in detail to us, and gave us her mobile number to contact her if we needed to (we didn't as everything was perfect).
It is described as a studio, which gives the impression that it is small, but it is far from small and in fact was there more space than we needed. There is a separate, good-size (medium to large) double bedroom with a large wardrobe with hangars and drawers, and room to place a travel cot comfortably.
The bathroom is separate down a long corridor and is very clean and modern (it seems brand new) with a double-size shower which is very powerful, and there was no problem with hot water. I would described it as a large bathroom, again with more space than is actually required.
There is a big TV in the large living/kitchen area, the kitchen has everything to cook with if we wanted to, and the oven is sparkling clean. There is a small dining table to eat at if you want to.
There is a partition that separates a small area of the room (if needed), with a comfortable bed which I believe may be used for guests, but for us was useful as an area to place our bags and change the baby. Round the corner hidden from sight is a washing machine and dryer which is really handy. The room is bright with a window that spans the width of the room.
There is effective air conditioning which we used briefly.
Joanna supplied everything we needed, including detergent for clothes washing, clean towels, toilet roll, washing up liquid, shower gel/shampoo etc.
We were able to use Joanna's parking space which we discussed in advance and understandably had to pay extra for - it is a very easily accessible secure underground car park. If you have lots of luggage there is a spacious lift which we didn't usually have to wait much time for (if at all). It is a quiet apartment block, seems very safe and people you do see seem friendly.
The location is great for public transport use - the train station is less than five minutes walk, and fast trains to the city take about 20 minutes. Although the local area is not particularly touristy, there are lots of shops (including a 24h convenience store), and a number of restaurants of various cuisines - mostly Korean), as well as a couple of bakeries selling tasty treats. There is a local shopping mall with lots of convenient stores, and the Westfield at Burwood is a short train ride away, or approximately 20 minutes walk - there is a cinema there as well as lots of shops.
Joanna's place had WiFi, but one of the best things about it is that it was portable, meaning that we could take a very small device out with us to have wifi when we went out (this is an absolute gem for tourists from overseas) - the amount of data is limited but it is plenty (we were there for six nights and had more than enough), and there is an option to pay for more if you use it.
We would highly recommend Joanna's place to stay!