1. Did you include the property management/leasing cost?
A: there is no property management fee. No body manages your property. You do that. If there any reason that your tenent will call you? Hardly any. In fact, they are more worried than you are if there is any thing breaks down. The leasing cost of one month lease is already factored in.
2. I didn't see you include the vanacy rate in the calculation? Is this true?
The vacancy rate is 10%, included in the calculation
3. The rent seems too high. What kind of the properties do you have?
High? why do you say it is high? Do you have any numbers to show us? I personaly invested my own money in some of the perperties listed above and I can say that all the numbers are real.
4. Is any tax advantage in China for the residental property investment?
Do you mean income deduction of the depreciation of your rental property? Chinese do not fill in annual tax return. Thus there is no way to get any money back from the goverment.