We gave our SEO company access to our Google Analytics. We want to check when was the last time they logged in to view our statistics (and possibly a complete log). Is there a way to check this?
You can only see if there were changes made on a specific account/profile/view. Go to Admin->look under Account for "Change History". But you can not see if they logged in.
Even if you could see a list of people who logged in, some SEO companies connect the user's Google Analytics account to their own tools where they use the data more effectively combined with other data they gather or, even more, they use exclusively their own tools. Therefore, there is a big chance they actually don't login into Google Analytics platform.