Hopefully someone who has done a lot of this will chime in but here are some thoughts I've accumulated over just a few dozen interior photographs.
If there are strong light sources in the room (e.g. sunlight coming in a window, candles, accent lights) your available light photo will often cause these sources to blow out badly. You want a flexible light kit that will allow you to balance the light in the room so candles still look like candles, and there's still beautiful sunlight streaming into the room, but also so that light sources don't blow out. As Neuro said, HDR might do this for you as well, but you should spend the time to find out what works and what doesn't. Also practice working with mixed light colors, e.g. fluorescent + incandescent
Also, edge-to-edge sharpness is important, so if your lens isn't up for it, either get one that is, or plan to crop and stitch.
I suggest you read some books on interior photography for more ideas; a quick search on Amazon.com shows a number of titles. Remember that interior photographs are often scrutinized in minute & technical detail.