I do a great deal of representation work in addition to year round in depth tax/business planning. 

For those reasons, it is very important that you perform an in-depth diligence process selecting and managing them.

Instead of "owner-occupied multi-family investor" (OOMFI) since this is also used with SFHs and condos how about we call it "Mortgage Regulation Manipulation Investor" (MRMI). 

There are COUTLESS threads that you can browse that discuss this topic in depth.

Being that it's a house on the waterfront, if this is on salt water and because it was built in the 40's, I would pay extra and get the most in depth inspection you can get.

@Mike Reynolds Thank you so much for the in depth detail on how these are installed and held into place. 

Appraisals are way less in depth and more of a quick look through and comparison to comparable sales to establish a value.I would be worried about whether or not the deal still works for you.

Most of the attorney "hand crafted" leases I see don't even come close to the depth and extend and must have cost a few bucks to create. 

Basically, about 60 feet (depth) of the back yard was worthless.

It's a great start that you have all the receipts and excel list, but you need to have a professional take a look if you want something that would be defensible to the IRS.To answer your questions: windows are generally considered structural so they'll be 27.5 year (unless they're a part of a 5 or 15 year asset - rare but possible), the floors depend on what they are and how they're installed, carpet and laminate are generally 5 year, solid hardwood and ceramic tile are generally 27.5 year, the deck could be 15 year or 27.5 year depending on how it was installed.If you'd like to have an in depth discussion on this and see some numbers PM me.