BUY FOUR, GET ONE FREE

That's quite a common sales promotion tactic, and you'd expect to see it for food, drink, and perhaps other everyday consumables. But for condominiums ?
The Prime 11 on Sukhumvit in central Bangkok is currently offering that deal for its new development, and I'm not sure how to read it? Obviously it's aimed at investors because who else is really going to consider buying four (or five) condos? Does it also mean that their units are already 20 per cent overpriced?