Unless I'm doing the arithmetic wrong, seven million yen per year would be very roughly US$70,000. This doesn't seem like a particularly high annual salary for an expat in Tokyo unless it's an English teacher, nanny, university graduate student employee, charity worker, etc. I wouldn't expect expats earning not much over US$70,000 (say US$100,000-200,000 per year) to be very interested in buying real estate in the Tokyo area.