When looking for an architectural visualization firm there are a few factors to keep in mind, including quality, price, HQ location, and its ability to meet deadlines. First and foremost, you need to receive a quality photo realistic rendering for your money. There are plenty of US based firms that will charge you premium pricing, for mediocre work, in short make sure your getting what you pay for. There tons of Offshore headquartered firms that have a huge language barrier, in which you will go through an extremely painstaking process to just convey your vision to them, and then hope once the rendering you paid for comes out as you expect, stick with firms Headquartered in the USA. Check references of a rendering firm prior to hiring them, you need to verify that they have a track record of delivering quality projects under tight deadlines. And Finally pricing, you can find allot of cheap firms out there, and on the flip side, there are a handful of companies charging 200-300% more for the same exact quality work that other firms such as Media Dream Studios provides at a competitive cost.