I ordered a 3rd party inspection and a list of items came back that needs to be (leaking pipe under sink, rodent infestation in the attic, downspout that needs securing, sewer vent pipe out to the attic, missing smoke detectors in a unit, loose material from basement wall which can compromise foundation if not fixed, etc...).

Multiple sub contractors with multiple separate contracts are not allowed..Repairs/Improvements must be completed by licensed contractor(s) as required by local/state municipalitiesRepairs cannot be completed by a related or interested party (i.e. relative, real estate agent, seller, broker, etc.)Borrower selects contractorContingency ReservesMinimum 10% is required.

Next...are Maintenace calls handled by your hourly employees or are do they 3rd party this out? 

People use STRs for small vacations/ parties/ random travel just as much as massively planned vacations. 

My guess is one fee you and your friend are noticing is a percentage cut from third party maintenance work.

Both parties agreed to 3 months.  

There are specific rules for 1031 exchanges including:The replacement property must be identified within 45 days of transferring the relinquished property.The replacement property must be received within 180 days after the transfer of the relinquished property or the due date of the taxpayer's tax return, whichever is earlier.Special rules apply for exchanges between related parties (defined in § 267(b) or 707(b)(1)).Real property located in the United States and real property located outside the United States are not considered property of like kind.Cost Segregation StudiesA Cost Segregation study is an IRS approved federal income tax tool that increases near term cash flow by utilizing shorter recovery periods for depreciation to accelerate return on investment.

Another reason may be that you appear unprofessional and interested parties are looking for a sweet deal like a landlord that doesn't screen or is negotiable on all their terms.

I’m comfortable sacrificing a bit on revenue in exchange for steady cash flow, lower expenses, and fewer headaches.However, if you come across a standout property with a pool and great amenities in Scottsdale, it could be very beneficial during spring training or for bachelor/bachelorette parties.

Quote from @John Jasko: Yes, and I was brought in to the deal by a 3rd party money wrangler who has since washed his hands of the whole thing.