For an independent dealer, DealerCenter is probably the best option. We switched from Frazer to DealerCenter in 2018 and haven't looked back. Our salespeople can use it effectively in about 2 days and we can send deals to Route 1, CUDL, and DealerTrack. They will beat or match the best credit bureau costs.
They are owned by Westlake so WL gets to see all of your data and deals. No problem for us since WL is a good lender for us and most independents. They have made several improvements over the years and partnered with other vendors with different tools or add-ons.
We use most of their products including the website, CRM, DMS Adverse Action mailouts, plus the soft credit pull tool. It would be hard for us to switch and every time we have sat with other vendors' demos they haven't offered anything more and it is always more expensive.
It is designed for independents so not an option for franchise dealers.