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Ok, assuming the max she wants to spend is 2000 then what would be the best, idk if she does but I told her it may last longer to get the better one...

On the Apple certified refurbished store, they have a 2013 iMac 27 with 1TB Fusion Drive, 8GB RAM for $1949. Something like this would work well for her:

http://store.apple.com/us/browse/home/specialdeals/mac/imac/27

For professional photography I'd suggest getting a screen calibrator if she doesn't already have one. E.g, Color Munki: http://www.bhphotovideo.com/c/product/798928-REG/X_Rite_CMUNDIS_ColorMunki_Display.html
 
For Ps:
you are correct that it utilizes quadcores and of course RAM.
For graphic design this might make a difference, but for editing photos (like a photostudio does) the difference is marginal from my experience.

For Lr:
I use Lr a lot with RAW files and I always monitor my system pressures with iStat and activity monitor.
RAM use is minimal (even with 4gb) and the (dual core) cpu usage hovers between 5 - 15% and peaks to 85% when importing and exporting.

I can say with certainty that at least Lr is definitely not a program that requires high system configurations.

The OP did not mention video and that is a whole different story altogether.

No real disagreement that Lightroom requires less than Photoshop but if one has both, then it would be logical to at least meet the needs of the software that eats up RAM and really can take major advantage of multi-core. Incidentally, Adobe references Lightroom as taking advantage of using more powerful processors and RAM. I'll just say I agree with you with respect to Lightroom being reasonable with less than what Photoshop 'needs.'
 
What hogwash. I have two 4gb machines here and they run multitasking Lr, Ps and Safari just fine.
Your statement is not based on reality.



And how does Chrome and or Firefox work out?


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The mini is a good idea, but the OP has no use for a quadcore.
But he could get a dualcore, stick an ssd in and upgrade RAM as needed.

I think the main idea is to get a 2012 refurb model. Doesn't really matter if the OP can't make use of the quad core chip now...or if ever. It's still a far better deal then to get some 21" iMac model for $1500
 
And how does Chrome and or Firefox work out?

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I think the main idea is to get a 2012 refurb model. Doesn't really matter if the OP can't make use of the quad core chip now...or if ever. It's still a far better deal then to get some 21" iMac model for $1500
Chrome and Firefox work just fine. They are not optimized for Mac however.

A brand new 21" costs 900€ here, while the 27" costs at least 1500€.
I think the base 21" is a good deal.
 
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