some sites 3000+ a day some sites a couple hundred - depends on the site and what they're selling - Can tell ya, in the travel industry - it died with the US crash.....lol was getting 1800+ a day a month ago now as placement gets better and continues to grow - traffic continues to drop like a rock ....ouch. 700+ keyword terms in the top 10 and under a couple hundred visitors a day - just shoot me
Can't tell you about real estate in Au - can in Central and south Florida
But you can get a pretty estimate of what you should get with decent placement
For example so far for the month of October there were 210 searches on google for "real estate new south wales"
I'm getting ready to do a realtor site for a company in the Dominican Republic "dominican republic real estate" 8,100 searches so far this month - I'll grab 2000- 3000 a day from that
Go here -
https://adwords.google.com/select/KeywordToolExternal - put in your term it will give you a good estimate of searches for the term.