The pattern is that an investor (Chinese) starts a project, gets a bunch of people to buy into it, a shell of a building is created and then all the work stops and is left for dead. Usually stops because someone in the chain of command didn't get enough coffee money.
Nha Trang and Da Nang are popular beach areas and rife with these sorts of things, but you also see it all up and down the coast as well as in the big cities.
Da Lat has been completely ruined over the last few years. People post before/after pictures and whole valleys that were filled with trees or farmland are now replaced with houses. It is a short enough drive from Saigon that it makes for a great weekend escape. Except there is really only one mountain road into the place...