Yes it is a money pit, but a very rewarding one, I have just built a cen matrix with a vspec and dsm 2, its a good start to racing i believe and it cost me about $1400. I had to buy starter box and gell cell and charger plus all my batteries and stuff, so it does add up but once you get those costs out of the way its ussually smooth sailing. If you just be careful when you start out and dont try to keep up with the faster guys, just find your style first you wont smash as much and it will be cheaper for you. As for second hand, buyer beware, its pretty easy for a seller to clean up a tired car and say it hasnt been used much......I'd stick to new if i were you. In saying that they can be usefull for parts, add up the cost of the things you think you might break and cant do without and you can compare this price to just buying a second hand rig and having every single part you need. It sux when the weekend is cut short coz an unexpected part gave way and you cant get a replacment.
anyway, you say you want ease of use, RTR might be the go for you, no building just fun straight up, if you are inexperienced is a top of the range expensive car going to help you? probably not, its better to start small and make your mistakes on something less expensive before you go the whole hog. good luck anyway.