Here''s my situation. I purchased a rental property in FL in late August 2019. The property was brand-new built in mid 2018 but evidently was not fully completed in the inside of the house (for whatever reason) until 8/2019. So the certificate of occupancy was not issued until early 8/2019. When I purchased the property in 8/2019, the house hasn't been appraised by the local tax appraisal office, so during closing, no property tax was due on the the building, only the tax on the land. 

The tax appraisal office finally appraised the property in 9/2019. In 11/2019, I received a letter from the tax appraisal office saying I owe a lump sum of property tax for the entire year of 2019. They did not prorate the tax for me from 8/2019 to 12/2019 since I purchased this property in late 8/2019. This really put a lot of strain on my cashflow since I have to pay the entire year of property tax in 2019.

Here's my question:

1. Isn't it the previous owner's responsibility to pay for the property tax from 1/2019 to 8/2019? I did not own this property during this time. Why do I have to pay for the property tax for a house I did not own? My property tax for 2019 should be prorated starting the time at which I purchased the property. 

2. The previous owner is trying to argue they are not responsible for it because the house did not have the certificate of occupancy until 8/2019. The tax appraisal office argues the house is physically built already since the beginning of the year, so they have to apply the tax starting 1/2019. 

I'm totally confused. I need help on advice from BP colleagues. I want to make this as simple as possible because I already spent too much time trying to figure this out!

Thank you in advance for your advice!