You want a mirrorless vlogging camera and an external microphone that capture crisp video and clean audio from day one. Buy a solid setup now that lasts for years, so you are not upgrading again in six months.
Look at camera supply stores right now because manufacturers refresh these lineups every year or two. When a new body drops, last year's model takes a price hit while keeping nearly identical video quality, making it the smarter buy.
Remember that the 0% intro APR for 15 months on purchases is a deadline, not free money. If you still carry a balance when those 15 months end, deferred interest or standard purchase APR will kick in on what is left.