For a more accurate answre to your question I recommend you try the Miami Dade Tax Estimator http://www.miamidade.gov/pa/taxes.asp
You can lookup the property's assessed value or manually input the purchase price, reduce it by your exemption amount (probably 50,000 if your homesteaded). Multiply this number by the milage rate and divide by 1,000.
The propeerty tax is approximatly 2% of the assessed value of a property in Dade county. So yes, the lower prices have led to lower property taxes. And the ther factor that effects tax is if the property is you primary residence. If so, you can take the deduction for that which brings it down even furher. I cannot really advise you any further about taxes, as I am not an accountant, but that is the basic information regarding property tax here in Miami Dade.
I would be glad to assist you with your search or any other questions you may have.