Plumbing, bathrooms and kitchens are also a pain.If you can get parking and meters to supply the numbers you want those two items are also important!

Traditional financing.

I understand the concept of having your contractor go in and getting an itemized scope of work, estimate materials and labor, but by the time this is done, one of you other OOS investors already swooped in and took the deal ;)   As we all know...a good deal will go quick, so I think the skill of being able to quickly estimating these rehab numbers when analyzing a "good" deal,  especially being out of state, is absolutely critical. 

For the main items called out, did you talk to a licensed contractor in that trade to ask them what the estimates to repair would be?

As far as theft...I don't know if this makes you feel better or worse, but equipment manufacturers use one key for every item they produce.

My first few inspections were helpful to help understand building systems and routine maintenance schedules (don’t have to worry about that stuff when you’re a renter.)Sadly inspections afterward, for investment properties, only turn up obvious items that’s hard to miss if you personally walk the property looking in the nooks and crannies.Rot, poor wiring, improper framing, water leaks, etc that are behind the walls is when I’ve gotten into trouble.

That being said, we have mostly put aside the thought of using traditional mortgages because they all report under us personally, and we're limited on how many mortgages we can have...plus the debt to income ratio will look skewed for us personally with all the mortgages. 

I always budget 15% for overages, unforeseen upgrades, and punch list items.

That is when you will either embrace non-traditional lenders, hard money or private money; or you will need to learn creative finance. 

These items are going to have the biggest impact on your returns.