I had a job for a short time with a recruiter/headhunter firm, many years ago. What I remember best about the training was that you never ever speak ill of a former boss, even if he deserves it. To the contrary, you heap praise on the miserable SOB. The rationale was that you won't get hired if the prospective employers fear you will end up trashing their reputation later on.
. . . the interviewer will wonder why you're applying for the job and will probably conclude you're after money, not a career
This, to me, is the most difficult problem with interviews. Of course I'm after money. If I didn't need money, anything I chose to do, I'd do for myself, not some company full of rules, pressure and politics. So I have to lie, convincingly, that I really give a crap about the employer and his goals.