I came across this by accident in a local supermarket, and as such wasn't expecting too much from this at all. It all seemed to start well. There was a palpable sense of dread, of something terrible about to happen, this was largely created by the cinematography; the camera would pan to a shadowy corridoor, or up the stairs, and linger there silently, as if waiting for something. And then the early scenes of the demons were pretty good too; you don't get to see much at all, a bulbous eye, a bit of blood and a whole lot of shadow, which is obviously a good thing for a film with a miniscule budget. The plot, however, needed a lot more focus: the makers couldn't seem to decide which way it was going: perhaps they were trying to disorientate the viewer as much as the protagonists, but this is probably giving them too much credit. They perhaps thought the ending was clever but in fact it just ends up confusing everybody. There are also a lot of unanswered questions - is Sarah dead? Were the newspaper articles of terrible deaths premonitions? Did Anna the pregnant tenant really suffer the terrible fate we saw happen to her? If it didn't, where did she go? Why salt?
So, to conclude, initially promising, but ultimately disappointing. I will add though, that the makers could well be ones to watch out for in the future.