12cfm @ 90psi is what you want. Make sure that's what its rated at.
I have an upright twin single stage that pumps 9cfm @90psi. Works fine for everything except my cutting wheel. It barely can't keep up. Works great on short cuts but it will drain the tank if I keep it running.
Single Stage high volume vs. 2 stage high pressure is your choice. I prefer single stage.

Flatto
12cfm will keep you out of trouble for most things and the advice you got about high air useage tools is right. Sounds like the unit your eyeing off will be fine.
Just to throw in my two cents.
I bought a cheap china spec 17cfm compressor for $750 over 10 years ago.
It has never had an inch of love in its life and it still goes like it did new. It runs everything fine, has plenty of pressure and I still reckon it pushes the 17cfm free air delivery it did the day i bought it. I recently ran two blow guns off it for about 4 weeks straight and it just took the abuse and kept going.

Sure a fancy brand compressor (westair, sullair, atlas copco etc) are much better built but for the money, go a cheap chinese made unit and get a 17cfm unit. You wont regret it.
Plus, I personally dislike Stanley tools. Their after sales service (Stanley that is) is crap, and if you want to return "lifetime warrenty" tools you will need to wait weeks for them to get back to you. And they own kincrome too.

Ok, so I spoke to one of my mates about this today to double check, and he has told me that the Stanley air compressor will be able to paint fine, so long as you take it slow and go piece by piece. He painted an engine bay with an air compressor with similar specs.

Some air tools that require constant free air like a sander may struggle with the Stanely, but it should do the job. Just check the air tool specifications when you're buying them and that they don't exceed the compressor specifications.

12cfm is equal to about 330l/min. That's the minimum needed for a good, professional job, just to be clear. I'm not a painter though, so I can't give you the specifics as to why that is.

I'm basing my research on personal friends who both work with them professionally and for their own stuff at home. 190l/min is possibly enough to do panel by panel or the odd touch up, but I was told that even with 250l/min it would struggle to do a decent job at painting.

That Stanely unit is definitely good value for money, but you might end up buying another one in the future because of frustration and waiting time. I really think you'd be better off spending the extra cash now and just buying 1 good one.

I have had my eye on the stanley ones from supercheap auto. 2.5hp belt drive and 190l/min FAD. Not sure how that relates to your figures or how i convert it? Seems to get good reviews. From what i have been reading some people over estimate the power they need upon advice from tradies who use them all day every day for commercial use. If your only spraying 1 car (and a small car at that) and you take your time doing one panel at a time you prob dont need all that much power do you?

Thanks
Trav

My research has shown that you get what you pay for with Air Compressors, and you'll need a minimum of 12 FAD for a decent spray job. I'd also recommend a belt driven unit so you don't send yourself (and neighbors) crazy from noise. Unfortunately, I think you need to double your budget to find what you're after.

This is the one I'm planning on getting next month:
http://www.machineryhouse.com.au/C340

It's a good quality unit, and should last a lifetime if well maintained, however even this won't do a good spray job though as it's only 8.4 FAD.

Does anyone have any tips on good air compressor to buy? What types have people had and good/bad experiences? Trying to pay less than 300 or so. Going to use it for all the usual grinding, sanding and painting.

Thanks
Trav