Duval County Property Appraiser: https://paopropertysearch.coj.net/Basic/Search.aspx This is a good place to start investigating properties you own, for physical data, public recorded information, tax assessment information and even comparable sale information

City of Jacksonville building permits: https://buildinginspections.coj.net/ This is a good place to start investigating properties that you may be interested in buying. It will give you official listings of permits that have been pulled on the property for improvements, updates and repairs. It will also indicated whether proposed improvements were actually completed.