I use my iPhone 5 now, it's got a great camera on it. Before that I used a Samsung that was about, £120 can't recall the exact model. The Nikon coolpix is around £100 and is 21 mp, I'd say that's do the job.
its a question how you suitable define and whats your claim. when you say small rooms and low light and portfolio my answer is a used SLR cam, a 10mm superwideangle and always a tripod.
I use my iphone 5 for work pics. Got great Panoramic options. There are also Panoramic apps out there for older versions. Would never take my SLR to work. I'd end up sitting it at the side & standing on the bag.
Here's a quick Panoramic shot I took today. You can take your time to get a perfect shot.
Here's a better pic I took the other day down at the beach when I finished up early & the sun was out