“The vast majority of Housing items are (and will continue to be) earnable in-game. Only a small fraction is available for purchase from the shop. Comparing this number against collectibles such as mounts is a good metric here, with more than a thousand mounts earnable in-game and only a few dozen from the shop.”

https://www.theverge.com/news/816714/world-of-warcraft-player-housing-hearthsteel-currency