It's going to take a lot of money for startup, especially if it's an indoor track. Are you going to be running carpet, on-road, or off-road? Also, I would do as abadk9420 said and check out the area for LHS. You want to see how many hobby shops are in the area, how much interest there is in indoor racing, and what scale most of the people are running. If 80% of the people run 10th scale, then I would think the track would do better running tenth scale because a lot of the people already have the equipment that would be needed, and that will allow you to start off good, whereas everyone interested in racing at your track would have to buy 1/16 equipment and not use their 1/10 stuff, so I think startup would be slower. Now these scales listed are just examples, I have no idea what scales are popular where you want to build a track. This is where research of the defined market area would come in. Also, you might not want to build a track 5 minutes away from where there is a successful track already running. These are just some things to check out.