Is it best to work on one piece at a time, or many?

I will be getting my grandmother's piano shortly. I haven't played before, though I have played a number of instruments. I will likely end up taking lessons...at least a few, but between the books and the videos from this site I imagine I can get started. Obviously a teacher is best for quickly pointing out bad habits before they start....so I don't need to know that.
What I am curious about, however, is whether it is best to focus on one piece of music, or work on many at a time. I have a list of stuff that I've wanted to learn for a long time...a number of Bach and Mozart pieces....Linus and Lucy of course....The Heart Asks Pleasure First....etc. Would it be best to do practice drills and then focus on one piece of music, or would it be better to work on a number of pieces at once? I would likely end up working on a few pieces just simply so I don't get bored, but I am curious what the general thought is on this....???

I would say that it's best to work on 1 piece at a time when you're just starting out, although if you are just dieing to learn 2 or 3 piece that won't hurt you to much as long as you make sure you finish them. Make each piece your obsession, master it and then move on to the next one

I think there is some value in doing both things: "playing around" (sight reading a lot of different things) as well as focusing on one piece. What's important in all the work is to remember to take pleasure in your piano playing NOW as well as any improvement planned for future. Anyway, this is how I approach it. My challenge is to work harder on one piece - I've got the wayward sightreading parent down

Best wishes,
Bill

The perfect amount is 2-3 pieces. That way you can practice without getting tired of playing the same over and over again. And at the same time let your brain work in silence with the other piece you've just practised while you're practicing the other one.

Ofcourse this also depends on how hard the piece is, 2 pieces can be enough, and 3 too much. But I find it really difficult to get any progress when I do 4 or more. You'll just find yourself struggeling to get the pieces done, and it seems that there is very little progress. The most important thing when starting a piece is finishing it so you havent wasted any time, easier said than done.