When a loss was incurred I accepted it as a cost of investing without thorough investigation and or the percentage probability of an unprofitable outcome.  

She's not going to have any leg to stand on in court if you get that far unless there's some explicit language prohibiting the owner from assigning responsibilities to another legally authorized party, and I'm guessing there isn't if another PM company was maintaining the lease and provisions - and the fact that the tenant was voluntarily working with the other PM confirms the acceptance of an authorized agent even if it's not explicitly stated, the same way if you accept rent from a tenant after a lease expires you imply acceptance of the lease terms continuing (which is why you should always have a holdover provision). 

Scope of WorkThe Subcontractor agrees to perform the following work (“Scope of Work”):Detailed description of tasks and responsibilities.Exclusions: [List any exclusions here].Materials to be provided by: [Contractor/Subcontractor].Reference drawings or plans: [Attach if applicable].2.

I think understanding that will get me more accepted offers. 

New occupants will be coming soon, but in a 3 family, i have set of excellent student tenants that renewed.That said, many landlord insurance policies have exclusions for students, so I am trying to gather info on updating a policy to consider the fact that the building is only going to be 33% student occupied.  

Although these platforms tend to accept bigger deals from sponsors with a lot of experience.

What I love about them is they will even accept the higher lease amounts over the market rents if we can show first month's rent and security deposit.

Even still, it could be said that I've still lost money due to my time on the tools instead of prospecting as a real estate agent (the cost of lost opportunity).If you can truly do 80%-90% of the work yourself (at acceptable quality levels) and you aren't sacrificing your time where you can get better returns for your efforts, then yes, it can work even up here in Canada.

The parties will jointly appoint an acceptable mediator and will share equally in the cost of such mediation.

It's important to get started on these as soon as the offer is accepted because the municipalities can be slow to respond and schedule the inspections.