I bought a primary residence house last year which I am not planning to house hack.

2) You did not ask for a PAYMENT PLAN IN WRITING WITH SPECIFIC PAYMENT DATES & AMOUNTS AND COPIES OF PAYCHECKS!

If you plan on living there a while, an extra living space would be great, but if you plan on selling it soon, I don't think it's a great investment of your time and money. 

What would be your plan for the property?

The plan would be to market the bottom level weekly during the peak season and split the off-season rental monthly and weekly.

Plan to re-fi down the road and create entities then to put it in, and fully keep it separate.

Very comfortable with taxes, but haven’t done tax work for years, so sometimes I seek advice on things I’ve forgotten.No one is going to do the level analysis and planning that I do with my own taxes, so I’m fairly certain I’m saving a significant amount of money in legal tax avoidance. 

A local RE professional should be able to provide this information to you as well.In New York, we deal with this scenario frequently and oftentimes it does not make sense to legalize ADUs because the permit process is extremely lengthy, the cost is high (sometimes $150-300K for 1 ADU unit), and the potential increase in property valuable is not worth the risk.If you already have an approved permit/plan and can get your renovation down to $80K, you may want to consider this project if the ARV is say north of $800K.** You should also look into any potential property tax increases associated with this change.

Thanks Jason,Yes, that is certainly the plan.

I will be in Tampa in a couple weeks and plan to explore neighborhoods a bit more.Trace