Quote - Mea Culpa!  I rechecked the website, and don't know what I'd been previously looking at.  Blender is free.

STRAW POLL QUESTION: 

At its least expensive, Modo 501 is $837. from Novedge.

 

My two cents:

If I had that kind of money to spend, I'd put it on ZBrush and Topogun and come out $37 bucks cheaper. Combined with Blender, which can do everything the big money titles can do, (just youtube the short film Sintel to see what Blender can do) you have a complete animator's studio right there.

You'll need a wacom tablet for ZBrush (or a tablet of equivalent quality), but if you're already working in photoshop then you likely already have one. 

And the only reason I add topogun to the mix is because z-brush's retopology tool is more frustrating than its worth. (for now, though I have confidence that zb 5 will solve that). 

Unlike most other software, Pixologic has always provided their customers with free software updates, so once you purchase zb, you likely will never have to pay for their upgrades, even as the price of their software increases. (That may change with zb5, but if their previous track record holds true, it won't). 

It's doubtful that you'll find one package that you stay in from primitive to completely finished and primed animation. Many artists jump back and forth from one package to the next in their pipeline, depending on what they need to do at the moment. Find software that you're comfortable working in and learn it through and through. Programs like Zbrush and Mudbox have revolutionized the way 3D modeling works. The days of point pushing are quickly becoming a distant memory for many. Understanding good topology is key for any 3D artist, of course, so learning the traditional methods of how geometry should be laid out for proper rigging is still vital, but don't waste your time and money trying to learn a bunch of different software that you likely won't have any use for a year or two from now.