If landlord was to replace carpet with our security deposit does it, by some type of law or anything in Florida, have to be of equal or lesser value than the carpet originally in there? Or can he just get really fancy carpet and charge us up the ***?
He can buy whatever carpet he wants.
Replaced carpet has to be reasonably same quality carpet. Since you have no knowledge of what was paid, the quality/pile/density, etc. there's really no way you could argue this. But generally if a renter is the type of person that damaged a carpet enough to need replacing, they shouldn't be arguing the matter anyway. These kinds of renters either have kids or animals that have destroyed it, or they themselves did it and had no regard for what happened afterward. In such a case there's really no one that would blame a landlord for anything he'd do to fix the place up afterward. Don't let yourself be one of those types of renters. It's supposed to be your home albeit temporary...it's not an animal crate.
The landlord can install whatever kind of carpet he wants. What he can charge the tenant is a different matter entirely. The tenant is responsible to return the unit to the same condition as when they moved in. This means the landlord cannot charge the tenant for redecorating, upgrading, and/or renovating the unit. Yes, the carpet should be about the same quality as was already in place if the landlord is attempting to charge the tenant for it. In addition, the landlord can only charge the prorated amount of life left in the carpet, which is typically estimated to last about 10 years. Meaning, if the carpet was already 5 years old when the tenant moved in, he could only be charged up to half the cost, even if he destroyed the carpet. If the carpet was over 10 years old, the tenant cannot be charged at all, as it was already considered as having to be replaced. This is a very, very loose rule, though; a judge may not necessarily agree or may consider the life of carpet to be closer to 20 years. Certainly, carpet can remain in good condition for that long if properly taken care of. Hopefully, you have move-in pictures dictating the condition of the carpet and what quality it was.