It varies by region and country but the big underlying factor is not enough new homes are being built. It’s creating an artificial scarcity which is driving up prices. Some other factors come into play depending on where you live. For example, I’ve read in America that a lot of the homes are being bought by trust funds and big corporations that can just overbid everyone. Now there are even less viable homes to sell. Here in Canada, we have a big problem where our federal government brought in a large amount of immigrants for it’s Temporary Foreign Worker program and it’s foreign student programs which created a big spike in population, especially in the major cities. The local governments are responsible for house building and didn’t do anything about accommodating a bigger population despite them knowing it was coming.