That's the red flag for me.

As for your negative cash flow situation, being in the red 900/month is not a good place to be in, especially considering an emergency can happen at any time.

Be suspicious of these red flags: any last minute changes just before closing, anything sent via email, anyone insisting on using their own title company or notary, any title company or notary that your closer/agent hasn't used before.

What are some red flags to watch for when interviewing Property Managers?

Nicholas,Its a beautiful property. 

Watch out for fine print that requires an additional fee at closing - this is a huge red flag and how most flat fee companies make money.

If you can swing hiring a PM without putting you in the red on cash flow even better. 

Going by the zestimate is a red flag.

Quote from @Luke Carl: You get what you pay for here  Meaning too low cost would be a red flag?

This seller also owns a really beautiful parcel of land next door that they're willing to include in the sale.