Typically HOA fees don't exist in rentals where as in condos that's an extra fee you're paying every month in addition to your mortgage. The $400k condo is going to have a substantial HOA fee.
I only have knowledge of my local area, but for condos around the $200k price range here have HOA fees around $500/mo. That would put him right back at a wash for monthly price if they didn't put any down payment on the condo.