How many models do you have of the same subject?

I have always wondered why someone would build heaps of models of the one subject. And I'm not talking about the second, third or even fourth model of a P-51 in your collection.

We all have multiples of the same model, but the kit may vary in:
- manufacturer
- OOB vs aftermarket vs scratchbuilt
- scale (eg a/c in 1/48 & 1/72)
- subject depiction (eg use of different decals, era's, refit/config's)
- display (eg waterline vs full hull)
- etc.

But I've seen some "Phantom Phreaks" and "Messerschmitt Maniacs" whose collection ranges into the high twenties, and possibly higher [:0].

I personally have 2x USS New Jerseys & 2x Bismarcks (diff scale & manuf.), 2x P-47s & Corsairs & F-16s. And thats it. I dont avoid buying multiples of the one model nor kit, I just like the variety - although I'm only 23 so there may come a point in my lifetime that I do more of the one subject .

How many do You have?