Either go all-in like Brandon suggests - 100% business use and super depreciate your already rapidly depreciating hunk of metal to help offset the awesome income otherwise being generated from your business - or drive the cheapest vehicle that will get the job done and track your mileage.  

Rough estimate would be 2k-4k for a metal exterior staircase.

Install metal kickplate and paint door and frame. $150.00Deck lower deck needs to be scraped and painted. $250.00Deck over top of parking area 15‘ x 12‘ Replace up to five deck boards 5/4“ x 16‘ $125.00Composite rails need to be scraped and painted need to use special primer/2 adhere to composite. 80 linear feet equals $160.00Replace broken and door missing 2 x 2 pickets.

First, you don't have the legal right to alter the property since you don't own it and you haven't even met all the closing contingencies yet since a Loan Commitment has not been issued. 

Do not let someone move into a property until they've met all requirements.

It needs at least part of the metal roof replaced and electric upgrades inside and all new drywall thruout.

They decided to use 2 metal shears wrapped in electrical tape to jump the 2 hot lugs in the meter box to the 2 lines that fed the house. 

Might be worth it to use the metal door/window blocks that you generally have to hire a company for. 

You can confirm that they met all requirements, if that is their concern, but ultimately another applicant was chosen. 

I used Bear Metal Welding & Estrada Fence in Evanston (BP doesn't allow me to post the phone number, but you can google it) in the past.