Just looking at street view of the house again. According to BR, KR left through the garage.
Unless the garage door was open at the time, it seems an odd exit choice. She would have had to open the remote garage door. (Mine is as slow as a wet week.)
Far easier to just walk out through the front door if you were leaving in a huff.
I initially thought this was strange too, Oz Jen. But maybe not so strange if she wanted to get something from her car before going for that walk to "clear her head"?
Also, after some reflection, I think BR's statement of what Karen did prior to her disappearance is not so unbelievable in my opinion. They had the argument about the shop and the finances. She went upstairs (To get something? Maybe her handbag?). Then came downstairs and told BR she was going for a walk to "clear her head". Went out via the garage in order to get something from her car first? (What? Sunglasses? Earphones for her smartphone?)
I also don't think it's unfeasable that BR would know what brand handbag or purse she had since he works in the rag trade. Especially given that these items were not cheap. We also don't know that it was him that told the police what brand handbag or purse she had (maybe it was SR that told them?)
I personally have questions about the $850 she was reportedly carrying on her, which I know has been discussed on this thread before. What if that money was the store takings from the day before which might explain why BR knew the exact amount of the money, and also why she was not yet at work. Could she have been waiting for the bank to open with the plan to deposit the takings prior to going to work?
The fact that she was dressed ready for work and carrying her handbag does not preclude her for going for a walk, in my opinion. Not if she left after an argument wanting to clear her head. She might have been planning to come back after her walk and leaving straight for work in her car without going inside the house and risk seeing BR again. Especially if she was angry.
There is obviously a lot that we don't know. So this is all conjecture.