Maybe it's a processing fee, an application fee, etc?  

Even with guaranteed rent, it's important to thoroughly vet applicants.

I  tried several time to request application to get my money back but never got it. 

Look at the application, start pricing third party flat fee services for each step.

For the nuts and bolts and real-world applications, I would lean on forums like these and studying or talking with other successful investors. 

As for property management software, options like Hostaway or Lodgify can streamline bookings and communication.

Be diligent in your application process and verification. 

We just fixed up the house and have it on zillow with several applications in 24 hours. 

I have actually been thinkin about cutting losses honestly, I am not sure this is the best investment I could have made as my first but worried about how much of a loss I would have to take.It is meant for S8 for sure, I would have a stringent application process, and give the neighborhood a C from my research.I invested there because it was the first deal that basically fell on my lap where the mentor works with agents that Seller Finance deals, it was only $3k down and had thought the proximity to St.Louis would be attractive to tenants also.I effed up on waiting to post for rent until after all repairs and the COO for sure.  

What is a good system to create around standardizing rent increases where applicable / best way to communicate it to the tenants?