You don't need a large space, but you should probably have a dedicated and well ventilated space. It is the nature of airbrushes that they create aerosol particles of pigment that don't ONLY settle on the medium on which you work. That means that stray particles float around, get into your lungs and some settle on furniture, clothing, curtains, rugs, etc.

A garage is a good space as long as clean air is circulated around the area. In good weather, the outdoors is also good. If you really have to work indoors, then a space set aside for art work is best. A spare bedroom with a window, a bathroom with ventilator fan, you get the idea.

As far as difficulty, it depends on your experience. I have been drawing well over fifty years, using all kinds of media. I feel I am as good with a brush as I am with a pencil. But I never COULD get the hang of watercolors. I can get some decent effects, but nothing like the professional quality of my other forms of illustration. So, for me, watercolor is "hard." But that doesn't mean that it's a particularly hard medium. It just takes a kind of discipline that I'm not prepared to apply.

It's probably just as true of airbrushing. But I LIKED airbrushing custom tee shirts and tote bags. Perhaps because I liked it, airbrushing came easy to me. Just like I rarely need to pencil an inked line drawing first, I found freehand painting with an airbrush quite natural. But I also had the willingness to learn stenciling, resist techniques, cutting frisket and other techniques to improve the quality of my craft.

For more information about my experience with airbrushing, may I suggest you read some of the earlier posts on my blog.

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