or did he say that fire has damaged the structural integrity?

One thing to make sure of while you are doing the fixes is that things are permitted that need to be (plumbing, electric, structural items, roof) because down the road when you sell your property disclosure may ask if items repairs were permitted.  

My cousin has a $75k/year job with excellent credit (he’s been working there for 4 years) How do I structure using his income and credit for a loan to buy a rental?

They'll miss many framing/structural defects and also many electrical issues.

I need a little help structuring a deal with an investor.

Hi Duncan, Yes you can negotiate during the due diligence stage and you can try to negotiate at any point in the sale process until close.If you end up not being able to move forward during your due diligence, your earnest money deposit should actually be fully refunded to you, provided you put in the contract that your offer is contingent on your ability to do your due diligence.There were several deals I worked on where additional repairs were found during our due diligence that necessitated negotiation.What we did was thoroughly explain to the seller the impact of the additional expense and then offer them the options of moving forward at a lower purchase price, or working out terms at the same price (owner financing/sub2/something else), or cancelling the agreement.Usually, the seller would choose to move forward at a lower purchase price but we definitely had parties choose to cancel or finance too.If they chose to move forward at a lower purchase price, we'd write up a simple 1-sentence addendum to the original contract stating the new purchase price and have both parties sign.You may want to include a deadline in writing of when the seller must respond by before you move forward with cancellation so you don't lose your EMD.

I’m looking for a structural engineer for a quick project in Ft Lauderdale.

I wanted to know if there’s a way to structure a sub-lease that would allow me to do the rehab, even though I wouldn’t own the property.

Others, depending on their structure and complexity may not be able to provide it until much later.

Sometimes you can structure a sale to minimize the tax hit, but it will depending on your complete tax situation.