I think it depends on the appraiser. 

It will probably depend on your experience and connections with lenders.

It was I believe 3k to sign up and then the cost to set up the LLCs for me was I believe $700, that partially depends on your state.

It will likely be a web of contractors, engineers, and architects, but some those are ultimately leading to the developer. 

I have a couple STR investors do this here in the winter months depending on the events coming to town

Here's a detailed guide on how to screen applicants: Application Screening Guide

I think it depends on the individual and opportunity.

I believe it depends on the lenders funding source.  

But ultimately the responsibility lies in my hands.I jumped on a seesaw of risk hoping that the momentum would catapult my bank account into six figures only to find out the hard way that flipping houses isn’t as easy as I had predicted.This house was purchased for $64,000 with an expected rehab of $100k to $120k depending on how much work the dilapidated and neglected house needed.The midwest is lovely but the houses carry the weight of weather storms nearly a century old leading to more damage than a beginning investor could expect.The appraisal came in at $225k for my lender meaning our all-in cost would be around 85% of the sales price worst case.

I know conventional lending could become an issue depending on the condition of the property.