A good interior paint job is often 50% preparation and 50% painting. Do not rush in preparing the surfaces in your eagerness to get at the brush or roller. If you do not prepare the surfaces properly, you'll be back with the paint brush or roller in a few months.
The reasoning here is simple. Every color in the visible spectrum can be assigned a number based on a luminosity scale (a scale from light to dark) from 0 to 9 where white is 0 and black is 9. Now suppose that the brown you are trying to cover has a score of 8, and the yellow paint you want to apply has a 4.
Cheaper then doing it yourself. Some would argue that if you're going to all the trouble to fully prep the car yourself, then why not just shoot the paint as well? Why get a shop involved? The answer is simply that you'll get a better job and for less money. Some would argue with this, but the fact is that if you've never sprayed a car before then your first car will have a steep, and expensive learning curve. Laying down an even, consistent coat of paint takes considerable practice. Also, paint and equipment is not cheap. You'll need to buy primer, color coat, clear coat, reducers & catalysts. None of these are inexpensive and you can easily spend as much in paint materials alone as the cheapest paint job at Maaco or similar shop.
Selecting a Shop. You should always get quotes from at least 2-3 different shops near you. This will give you a chance to not only compare prices, but to also check out the quality of work each shop has done. Ask to see cars they've just painted. Look for orange peel or excessive overspray. Do they mostly do insurance work or do they paint entire cars also? What types of cars are they working on? A shop that sprays nothing but old beaters probably doesn't inspire as much confidence as one that does insurance work for the local Lexus or Mercedes dealer.
What emotions does it produce?
Are the contours rough or concealed?
If you have a timber floor that's not particularly attractive or is made from a patchwork of old and new wood, paint makes the perfect disguise. There are plenty of choices - all the colours from Farrow & Ball are available as floor paint and Nordic Style offers an elegant selection, too.