How bad is it? Andy Milligan film (terrible).
Should you see it? No.
I'm including this mostly because it's constantly confused with another film called either "Legacy of Blood" or "Blood Legacy" - an odd bad film with John Carradine that I rather enjoy. This is Andy Milligan's remaking of his own "Ghastly Ones," which has a similar plot to "Blood Legacy," which is part of the problem. Three sisters and their husbands must spend a week at a mansion - in harmony with each other - in order to inherit their uncle's estate. Things get weird and then violent, but without the over the top gore of The Ghastly Ones (which may have been edited out). The camera is steady for once, in fact immobile. More restrained and more technically competent than most Milligan films, it's still not good but not endearingly awful, either.