I'm going to be shooting more Real Estate photography so I need a decent flash setup (4 flashes ideally) but I have no idea where to start. I'm ordering an SB-800 (I have a Nikon D50 if it makes a difference,) and I know I can get additional SB-600s and trigger them wirelessly but I really don't want to spend $1k on flashes right now. What are some options for cheaper flash setups? I don't know what I need, how they all get triggered, etc. Thanks.