The problem (as you have cited) is trying to understand what you need (you don't know what you don't know), where to get it, qualifying its source(s), and the validity and usefulness of all that.Pardon me if I've gone into this too much, but I meet many people with the same concerns that you are voicing and this is offered, as much as possible in direct response to your post.Please feel free to contact me if you have any comments or questions. 

I require proof of income, and verify it by contacting the human resources department of their employer in writing. 

Contact a local property manager.

Maybe ask for contacts with the PM and talk with them.  

Those companies you asked about are more for deal finding and direct contact to off-market sellers, is that what you are looking for? 

How do you connect with the right contacts or organizations to offer your property for mid-term rentals?

Contact a couple local PM’s.

I would also try to contact the code compliance department for advice.

I then ran a different ad and the cost was only 6 cents per contact. 3 cents higher than FB lowest estimate.

I am looking to build a house in lake county. pls let me know if there are builders whom I can reach out to?