Nathaniel,Because of the need for Pollution coverage by a Demo contractor, we are often using Specialty Markets that do a lot with the Environmental Firms. 

My overall goal as of now is to have a good amount of passive income to supplement my salary, be comfortable while giving my wife the ability to go back to school or pursue new work if she wants.

@Joseph SchommerI love the idea of having a steady but seasonal job and the supplementing with rental income, to me, flexibility is everything, you could take on bigger projects in the off season and reap the benefits during the on season!

Can someone recommend an insurance agent on the coast of Mississippi that also writes flood coverage?

 A lot depends on the age and coverage amount on the building.

Debt coverage, length of lease, remaining years on lease, type of tenant, among other considerations all play into the decision. 

There are programs out there that ignore your personal income and will even ignore debt coverage on the subject property. 

All institutional lenders require the coverage, and you should too.For the seller, the interest income will be taxes an ordinary income - so no tax advantage there.

A common thing to look for from those folks is someone with a Debt Service Coverage Ratio (DSCR) option.

I believe they are UK based, not that it has anything to do with coverage.