You can close the stairs to form a separate space and put the bodhisattva statue on the stairs. But it's better to make a shrine or something, so that the dirty things upstairs won't fall on the Buddha statue. In reality, I met a man in the stairwell, because of the limitation of family space, and it felt good, as long as I was respectful.
There is nothing to rely on behind the desk;
If there are stairs behind the table, there is nothing to rely on. There must be a backer behind the table. If it's empty, it's hard to protect yourself. Such a divine table is undoubtedly bad for Feng Shui. People worship God to be blessed, but it is difficult to protect people, because the Buddha itself is difficult to protect.