Yes the vacancies are significantly higher in condos. I believe this is mainly due to late investors/condo flippers and developers putting inventory in the MLS.
I don’t know the impact either but the percentage of vacanices is nothing to get excited over as its not all that different from what is has been over the last decade. Before that there is no data.
BTW, above you stated that “We know that 30% of homes bought in the last few years were for investment purposes”. How do we know this?