My day job has software that contains a feature that could help with #4 and #5...To post an item the process is to enter it into the search bar and a list of previous items appears. 

Hello, my friend, hemlane is good, but you could also try avail, it has a lot of features as well and, as for me, it's a simpler interface.

But you will most likely not be able to get premium rates until you have a proven record in managing other peoples property.  

You won't be able to charge a premium for these items like you would if it was a STR. 

A really good episode of the Bigger Pockets Podcast on YouTube recently features an investor specializing in mobile homes. 

They have lenient credit requirements and require mortgage insurance premiums.

Check title records to see if they actually own those properties or have a lease for arbitraging.Use the California Secretary of State's business lookup feature to see if they are in good standing. 

This area often commands premium rental rates.Miami Downtown: The epicenter of Miami's business and cultural scenes.

We have a partnership with BP so you can get access to most of the features for free with your BP Pro account.

They were reducing the premium slightly for this loss of coverage.