I need to know if using rechargeable 9V batteries are allowed on the White Christmas train. I also need to know how many cars I can add to the four car set included in the kit.
You can use rechargeable 9 volt batteries in the tender of your White Christmas Express. The power supply that comes with your set is not designed to pull a lot more cars, If you want to pull more cars it would be a good idea to get a better Power supply. 2 1/2 to 3 amps would give good performance and some room to spare.