Try to put it all on hold the best you can. Say that you have some personal "doubts" and want to stop that ministry until you face those fully. I say to use the word "doubt" as it will automatically trigger them to make allowances for your delaying the ministry and the baptism.
Don't offer details. Be firm. "I will do my research. You already taught me how to do that." You may have to continue going to the KH if you are so sure you are financially stuck. But really, they can't make you do more, no matter what they say. If they are still studying with you, cancel at the last minute or the morning of your study a few times, then say that you were dealing with something personal. If they get mad, suggest putting the study on hold for a few weeks (which could lead into much longer).
Get yourself out of that financial bind. Work more, save more. Whatever you have to do. Find a different roommate who is a stranger or friend, but not a JW. After you leave that house, you don't have to bother with them. Drop them cold and say you worked out your doubts.