Florida tax sale questions

[James C.]

All,

I'm looking at some contiguous Florida tax sale parcels with multiple years of tax sale certificates which are all owned by the county. 

If I wanted to put them together do I need to buy all the back certificates for each parcel or just the latest year?

Also, if I buy just the latest year, what if someone buys the prior years? 

Do I need to buy subsequent years? Say I buy 2016 do I need to buy 2017 and 2018 before I do the quiet title? (I am assuming I need a quiet title suit)

If I buy 2013 in 2017 do I need to wait until 2019 to start the process for obtaining title?

Since the county owns the tax certificate and I buy the 2013 does that mean that the two year timeclock has already been completed so I can start the title process immediately? Or does the timeclock start when I purchase? 

Thank you, 

Jim