As for the triplex idea, it is zoned for duplexes and triplexes, it would need a new survey.

There are lots of online resources for survey creation. 

Building survey?

You'll need a survey, site plan, and pictures, plus about $500 and a month or two.In-place renovations would be grandfathered so long as you're not expanding the Gross Living Area.For further information, look the zoning particulars up on Municode and/or go down and talk to the building dept. directly.

It is in the flood plains and due to us doing "significant" rehab. they require us to have the property above the 100-year flood plane and we have done the elevation survey and all and based on that report, it would require 30 inches above. 

To knock down a house, you need a boundary/site survey, a survey that indicates the proposed new structure, a tree survey, an asbestos survey, a pest letter, etc.

I'm not sure what your land per acre is worth or what it is zoned but this can be done by an engineer or survey company for a few thousand dollars out of pocket. getting the second home on your lot I wouldn't do it that way. especially if you lack funds. 

Here's a little bit about what you'll learn:WHAT YOU WILL LEARNHow to assemble an all-star team that will set you up for success.How to fund an investment property with other people’s money.Expert techniques that will help you create a solid investment plan.Right now, we're getting roughly 4.5 stars (out of 5) on our feedback surveys.

Interest, points, application fees, surveys, etc. 

BP is doing a survey right now about this.In our 24 years of experience, the biggest challenge is owners not doing enough research and asking enough questions on PMC processes to perform their services.