This is what I did for a cabin I built in Gatlinburg:  We took a few royalty-free photos of the area off of the internet, and submitted them to an art site online whereby they make a painting of the photo.  

Many PHAs allow you to apply online, but some may require a paper application.

Rentmarketplace.com helps with the online application process.

I setup one QBO (Quickbooks Online) account to handle multiple LLCs. 

Theres a lot of place online to list like apartments.com, facebook marketplace, realtor.com, trulia, rent.com.

We currently have 105 units and are using a variety of excel, google docs/sheets/calendars, apartments.com (ads and rent collection), docusign and QuickBooks online (which we would like to keep). 

Go to Etsy and search for "rental property tracker," and you will find hundreds of nice spreadsheets to track 10-20 rentals, usually for under $10.Software has extremely helpful features like online payments, marketing syndication (click a button, and your property is advertised on multiple sites), electronic document review/signing, maintenance tracking, and owner reports.

Sadly, it’s sat on the market too long and I’m looking to get creative with bringing the attention of many buyers looking for a good deal on a property (online auction or something else with tons of attention??)

They are a huge online-only group and they loan up to 90% of home value. 

Check out other online guides available here: https://www.biggerpockets.com/guides3.