Indeed a few big DMS providers are the dominant players. It's somewhat similar in the automotive world. You can't build a car however you like... It's nice to think so....but there's a ton of regulations involved...and then you have to ram several perfectly good ones into walls and measure how crash worthy they are. You can't use the manikins from Old Navy...you have to obtain some very expensive dummies outfitted with sensors to relay impact stresses into monitoring equipment. Etc Etc. There's a lot more to building a car to sell than just bolting parts together. Now...if you are content to build one for your own personal use to drive on your own property..that's different. DMS providers have similar issues. It takes a great heaping hoard of people to keep up with the requirements of manufacturers. Parts Return Policies, Warranty Claims, Tax agencies and DMV requirements, Financial Statement changes, New Vehicle Model Years, and the list goes on. I wondered If I could design a "better" system than the big DMS providers... and eventually determined that there were HUGE barriers to entry. Sure, I could probably do "some" things better than the DMS providers...but it's hard to succeed on a very limited feature set. Eventually I figured...if you can't beat 'em...join 'em. -- make specialized software that integrates with the big DMS providers.