You can also listen in on Rob Abasolo's Youtube channel (Rob is one of the recent Bigger Pockets host) and you will learn a lot from him.If this group offers an opportunity to invest with them or their properties, then it may be worth the price. 

Dealing with warranty service is a pain in any situation but when you also have to deal with a tenant on top its even worse.

any lender wants to know how you plan to service the debt.

It likely is out of date as to cost as this info is quite old (my guess is 5 years but it could be longer):- Rent Recovery Service: offers flat fee service starting at $20. 3 letters start at $30.

I.e. say your plumber has a fixed $150 service call fee.  

Do you use any tools or services to automate the process, or is it something you manually handle?

Thank you for your service. 

I told them I wanted nothing more to do with them.Then they sent me a cancellation contract, but their customer service accidentally sent me the wrong one—saying they were going to refund me.

Are there specific lenders or servicers that are more likely to call these loans?

I'm not sure if I want to do co-hosting though.