I would sell my house if it looked like it would continue to drop in value. A lot of small rural communities in BC are losing their main industries, sawmill and mining, you get what the market will pay. What you paid for the house doesn't matter.
As far as , "locking in a loss" is a meaningless concept, although it seems to be quite widespread. A loss exists or it does not. Pretending that it does not come into being until it is "crystalized" is equivalent to putting one's fingers in one's ears and singing: "La, la, la! I can't hear you!" The analogy that comes to my mind is driving a car with defective brakes since, after all, the problem has not been caught by a formal safety inspection yet.
If the argument is that a security, on which a loss has been incurred, might yet increase in value, the counter is to ask whether it is more likely to go up than another security. The relevant consideration is not the previous loss, but rather the potential for future gains. In other words, a gain is a gain is a gain, regardless of past history. The market has no memory, nor does it have a sense of fairness, whereby it makes up for past losses by favoring historically losing securities.