Buying triplex zoned as a single family-HELP

[Michael Dumala]

I am under contact to purchase a property in Tampa, Florida. Looking to owner occupy, then rent out the other two. This "triplex" is listed as 2 single family buildings; each are an RS-50. The realtors (mine or the seller's) are not providing much information on this as they are uncertain. I don't want to get into something that can come back to bite me.....fines, violations, restrictions on future improvements needing permits....many possibilities for repercussions.  So far I have contacted lawyers, the zoning departments from Tampa and Hillsborough county. Everyone seems to say different answers and I am trying to learn as much as I can about these but I need to be able to find out for sure. We have 12 days to cancel contract and get deposit back and today is day 3. This is everything I have found out so far:

1 This is two buildings that are each listed as single family residences; the back building has a top and bottom unit all with separate meters. The property was built in 1925 and the current seller purchased and renovated it in 2017. It was already a triplex at that time. 

2  Zoning department could not find any variances/ conditional use permits/ anything suggesting it has been grandfathered in as a multifamily residence

3 The property has not been occupied since at least 2017

4 rezoning is a long, expensive process and the zoning department does not believe it would pass

Does anyone have any suggestions or advice? I am exhausting all of my options and no one is consistent on their answers for what is possible/ what negatives would/could even occur? How can properties exist that are "illegal" like this? I have seen multiple other properties like this as well in a short amount of time searching and feel it could be something I keep encountering. I don't know who to turn to to give me a confident answer.