Repair existing rear deckwhich consist of replacing board on rails and decking and secure deck properly from moving.3.

They all wanted to see at least 3 years of consistent work experience, which I definitely had, a healthy debt to income ratio, and of course a good credit score.

Go to as many local REIA meetings as you can, and be consistent about it. 

this is fairly common practice in low income areas Ideally you’d never do this but in some rough neighborhoods where everyone is on assistance it sure can help

What are some best practices?

Essentially, if you consistently pay business expenses with personal assets or pay personal expenses with business assets, any half way decent attorney who is suing you will be able to say "your honor, the LLC and the individual behave as though they are a single entity. 

@John Thedford and everyone: (Disclosure- I am not licensed to practice law in Florida, or anywhere else!)

I was consistently closing on small deals for 5 months straight and then the last 7 months of 2018 were flat lined.

The place seemed to generate at least $2K a month net after all debt and expenses consistently, and though the market seemed very small and unexciting, I was drawn to the promise of big cash flow.

Your contractor should have at least communicated this with you when before incurring the cost of the extra material, best practices is to provide you with a change order as an amendment to the contract.