Why would an investor take out an 18% loan to purchase a residential property?

I'm conducting due diligence on a building I'm interested in acquiring, an apartment complex that qualifies for a commercial mortgage. From the government's land registry, it turns out the seller purchased it with an 18% annual interest loan from RBC. It's baffling because it would qualify for a commercial mortgage at a more reasonable rate. The interest alone is double what the building generates.

Can anyone offer some clarity as to how it makes any sense at all to take an 18% interest loan to purchase a building? The seller will not budge on price despite being on the market for nearly 2 years, I'm trying to figure out, what exactly is their strategy or logic.