I'd highly recommend staying at Andréa's apartment! The location is fantastic - a short walk from the Gare de l'Est and Gare du Nord, and very conveniently located for exploring the city on foot or by metro. The space was cosy and clean. As noted in the description, the toilet is located in the hall, while there is a shower and sink inside the actual apartment. The apartment is located near a busy street so I'd recommend bringing earplugs if you are a light sleeper.
Andréa responded quickly to my messages and shared recommendations for restaurants in the area. A perfect spot for a short solo trip!