I inspected the property, created the scope of work, priced the material, estimated labor hours, ect.

Use the plastic plumbing material not copper to replace it. 

I could go on and on, but you should definitely hit Home Depot, or use online, and get familiar with material costs.

Whatever happened, it was late and the photographer had to work around the mostly-installed appliances and construction materials/tools/boxes everywhere.

I went shopping for flooring companies and found one that will install the "wood look" planks for $4.69/SF including materials and labor.

Tariffs are a factor, mainly on certain materials like steel, but not a huge factor overall   Without knowing many of the specifics, or finish out levels of your project, I would expect to be able to build something like this for around half of what you are being quoted.My guess is the reason for high quotes is that because the demand for construction is so high, and contractors are backed up with as much business as they can handle, they are throwing out very high prices.I would keep shopping, and if you have experience, consider GC’ing it yourself, and hiring the expertise in the places you need it.

I know I need to get solid idea of material cost, and this is the most consistent recommendation I've heard. 

Your Scope of Work Document should include as much detail as possible including:Detailed List of Repairs Plans/DrawingsList of Materials (SKU #s) & defines who's responsible for purchasing (you or Contractor)Payment ScheduleThe Payment Schedule defines the Payment Terms of how and when the Contractor will be paid on the project.  

Scheduling, skip tracing, data entry, photo editing, pricing supplies, transcribing calls, etc. are all $10 an hour items you can outsource pretty easily.I think local $10/hr tasks are harder to outsource like placing bandit signs, picking up materials, etc..

Finds the best tenant possible while also abiding by fair housing laws Is fair to all tenants and leaves everyone feeling like they were fairly considered Currently this is my strategy:List unit on a WednesdaySchedule everyone that calls to view the apartment for the coming Saturday or SundayAll scheduled viewings in 30 min blocksNotify the tenant when they schedule that it's on a first come first served basis so the earlier they get there the betterIf someone shows up to view the apartment and want to lease it, they fill out the paid application/background check there and provide other required material.