Privately-Owned Rail Cars
This is my "if I won the lottery" dream.  Which it would have to be, since everything about it isn't cheap. Purchasing a Pullman car then upgrading it to Amtrak standards will cost at least $300k. Any interior upgrades are on top of that (renovating the galley with modern appliances, adding central air since some cars used block ice for cooling). Amtrak requires you add 480v head-end power (but you will likely want a diesel generator too), door control/communication wiring, and to upgrade the braking system.Once you have your car and you have passed your annual inspection, you will need somewhere to park it, which usually means finding a short-line railroad or commercial business with a siding near you, and paying them a fee. Getting the car from there to the nearest Amtrak station will require you to hire a locomotive with crew (some tracks require a second car coupled to the locomotive so crossings & signals work correctly). Amtrak then has a whole schedule of fees they will charge you, from $4.09 per mile, overnight parking, fresh & wastewater servicing, transponder tags, and parking fees.You will want to hire a chef to prepare your meals and perhaps also a steward to serve the meals, make drinks, and take care of the staterooms. I'm not sure if they need to belong to the union since they would be your employees, not the railroads (but probably).For the less than 100 private cars in operation in America, why does Amtrak even offer this service? Like the first class section on an airliner, it's effectively all profit for them since the train was going there anyway and the extra fuel to haul it & supply power is minimal.  Personally I wonder why Amtrak doesn't offer a "Presidential" fare, where 6 or so people can book a private car and get truly top tier service.Here's what a restored Pullman car can look like:  https://www.youtube.com/watch?v=WdroQ4JqlYQ