Should I invest in a HRM with only 6lbs. left to go???

Let me start off by saying I over-think most everything! I only have about 6lbs. left to go to reach my goal weight, but have started doing the Fitness Blender videos, which are kinda hard to gauge calories burnt without a HRM. I've spent weeks researching which HRM's are the best, and if I pull the trigger and buy one it will be the Polar FT4.

Here's my question, should I even bother purchasing a HRM at this point? The only reason I would want one would be for the calorie counting since I only workout at home, but keep bouncing back and forth on if it's really worth the investment at this point. The weight is coming off and I'm toning up, so I guess I'm just looking for justification. I just give it my best "guestimate" at this point based on the Fitness Blender site, plug it into MFP and hope it's semi-accurate.

What would you do? Am I definitely over-thinking this?

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