So, it really depends on what you are trying to do. Firebase is not a relational database, and if you are going to have deeply nested data types and complex relationships - for instance Maybe spaces exist, and spaces have rooms, and rooms have availability, and you need to find all the spaces available at a certain time in a location - querying these relationships is much easier in a normal relational database. Firebase is fast and great for simple use cases, I've found it painful when trying to scale.