Any reason why you need to be at home? When I was in that situation I arranged for the viewings to happen when I was out so it wouldn't inconvenience me.
It's probably fine but I don't feel comfortable with strangers just being in my house while I'm not there.
I didn't expect there would be so much interest though, especially seeing how there are other apartments in the building that have been up for sale for 2 years now.
Any reason why you need to be at home? When I was in that situation I arranged for the viewings to happen when I was out so it wouldn't inconvenience me.