So far, we've pieced along different elements of this (different tax person each year, no LLC to one to now 2 this year, haven't yet used a bookkeeper...)trying to streamline systems and have a solid foundation for our fairly new and growing real estate portfolio. 

An added bonus I bring to the table is a decades worth of residential foundation experience.

It could be building deterioration... where the foundation needs to be repaired, or the gates, etc, etc, etc.  

The main guide lines focus on it being on a permanent foundation (Concrete slab), Hurricane tie-downs if you are in FL, GA, LA and a few other states, must be a double wide and not moved from another location.

We’ve put silicone sealant along the walls of the portion of the house that is affected all the way to the foundation.

Since they're part of the community, they wouldn't have to worry about window, roof, or foundation would they?

Recently, I discovered that I'll likely have to repair the foundation of my house to prevent any new cracks from forming through the cinderblock walls, however, I'm not sure other large expenses I should look out for.

You don't need to know everything to get started; you need a foundation to build on and the rest will come through experience and then refining your education.You can build a basic understanding of investing in 3-6 months.

For me, the first three things that happen on my builds is 1) site prep, survey, foundation/piling marking and temp power installation, 2) foundation/piling driving, 3) start of framing. 

My initial criteria is to look for newer built houses to minimize maintenance and upfront cap expenditure on major items like HVAC, Roof, Foundation etc..