How many pairs of climbing shoes is enough pairs of climbing shoes?

Asking for a friend who is prone to stress-shopping and may soon be home all day with a PayPal account and access to the Internet. 

n + 1

I disagree.

n -1 with n being the number of shoes your partner will leave you over.

Depends. I would say 10-25 pairs should do it. 

Kris Fiore wrote: I disagree.

n -1 with n being the number of shoes your partner will leave you over.

Happily divorced. Does that make it n-1, with n being the number I can purchase before I am unable to pay my bills with the remaining bank balance? I mean, my friend?

No idea about this. I have 11+ pairs and wanting more.

I have three different models, duplicates in each of them for the most part.

TC Pros for long alpine climbs or otherwise crack intensive routes  
Muira for cragging, sport and trad 
Shaman for sport cragging and the gym

I have duplicates of each for resoling. Except the Muira, but I'm about to buy a second pair so I have velcro & lace.

I too am prone to stress shopping online... Hang in there. 

Solutions are THE solution

3. A super comfortable pair for all day multipitch use, a tighter and stiffer pair with more toe point and heel tension for more technical footwork, and a pair with downturned toe for steep overhangs. 

3 pairs:

Cheap thrasher pair with durable, hard rubber for the gym

Aggressive shoe for single pitch sport climbing/bouldering (or at the gym if I feel like trying really hard)

TC pros for trad/multipitch/big wall (you'll notice this is the only category I listed a specific shoe, bc they're the bomb, accept no substitutes!)

3 pairs. 1 downturned hard rubber (I use the katana lace), 1 super soft rubber flat shoe for slab (I use the evolve nighthawk [the only good evolve shoe], and the last stiff and flat shoe used for crack climbing, I use a old mammut shoe that I had resoled with edging rubber. If you only climb one disaplin, like technical bouldering or over hung pockets, you might be able to get away with using one less shoe. Also having a pair of beater shoes for the gym will extend your other shoes lifetime.