Well Im not the most experienced but I house mine in a 10 gallon tank. Basically what your looking at if you do the prescribed tank maintenance to maintain high humidity your looking at spraying about once a day. Im not familiar with the daily maintenance for a tub what you would be looking at, but I have found taking 5 seconds of my time after waking up in the morning to spray his cage (your supposed to change the water out every day anyways) to be pretty simple. I like to check on him and see what hes up to periodically anyways so it hasnt been a hassle for me to use a tank.
Cheapest way is to probably go to reptiletubs.com though and use those. They come with hinge locks I believe and that is probably the way I am going for my next snake, and when i have to upgrade my ball to a bigger home because it is more cost effective.
My 10 gallon tank setup for my baby BP for all the hygrometer heating pad and so forth including the tank was about $120 so it wasnt too bad. I know Im kind of going both ways but they both have their advantages. A tank isnt bad or a hassle to take care of if you make the proper setup to hold humidity and what not. For the balls lifestyle and preferences a tub is probably the best way to go though because its not really a "viewing" snake. It will be in its hide pretty much all day,where all you will be lucky to see is part of his body anyways. Once again theres nothing wrong with the tank and it does have its advantages, but a tub is probably ultimately the best way to go. Its cheaper and suits the balls lifestyle and needs a little better.