Some of his numbers were a bit optimistic. I consider property to double every 10 years on average, he had it growing at 10% compounding - so a $330k property was worth something like $855k in 10 years.
jen your right, i didn't spot this at first,
if your compounding at 10%pa year on year after 10 years its over 2.5 times the original.
To double your price in 10years you would need an average compound of 7.2% or 2^(1/10) -1 * 100%
to double your house price in 7 yrs would need
2 ^ (1/7) -1 * 100% = 10.4% pa compounding