Does the car fit with the rally? I have been told it is too 'nice'.
Not too nice. You probably won't win outright on points or anything, but plenty of people have run the rallies with "nice" cars. Some examples: a rental Chrysler 300C, a few daily driven Mk. III Volkswagens, a few modern-ish Volvo wagons, a Porsche 944 stage rally car, and probably some more mundane cars that I'm forgetting. There was an E30 last winter, too.
You can bring any car you want, basically. Your difficulty, discomfort, and likelihood of having trouble are directly related to how many points you'll score at the inspection, which is where you'll rack up the most points. You can find the scoring info on the Rally site here:
I have never done a rally like this so I am not really sure what to expect.
In short, this is kind of a long-distance scavenger hunt. When you check in for the rally start, you'll get a rally book with a list of checkpoints and instructions on how to get points for them using Instagram. The checkpoints are optional and some may add considerable time/distance to your route. In theory, that will require on-the-fly route planning, but we know the type of people who do Lemons Rally don't usually think that far ahead. Anyway, the checkpoints usually outline a route or have a couple different optional routes.
Most of the checkpoint are usually bizarre, famous, or generally cool landmarks. Sometimes, they're weird little quests. This year, we have a couple of new things in mind to keep it interesting.
We usually will try to have a meet-up in the middle of the day along the route and another one in the evening at/near the recommended host hotel.