First off all Margherita is an amazing person! We had some very nice conversations and her English is really good too. I loved staying with her and I would definitely stay there again!
She gave me a detailed description of how to get to her house, which metro/ bus etc. It's ideal if you want to visit Rho Fiera, but also to visit the centre of Milan.
The bus stop is practically downstairs. Her house is clean, neat, spacious and very comfortable. Her cat is really quite, most of the times you won't even notice she is there.
The neighborhood is safe and quite, there is a supermarket a few blocks away, easy transport to other public transportation too. So I would definitely recommend staying with Margherita! :)