There are various applications that allow landlords to collect rent, manage payments, and disburse funds.

Piling on...all occupants who are 18 or older (or legal emancipated minor) should absolutely be required to make application. 

As a fellow West Aussie who's now living in the US, I can tell you this forum and most of the training/courses you'll see online regarding multifamily investment isn't relevant/applicable in Australia.

We accept all applications and in the case of section 8 the only real time we don’t is if the numbers don’t make sense with market rent vs HUD standard.  

I would first check city/county STR rules and HOA (if applicable). 

One housing authority wouldn’t even entertain the request, while another was open to it because it was an affordable housing property, requiring just an application for the exemption.From my experience, dealing with government agencies, especially when trying to save money or get financial benefits, can be a slow process.

However, without significant updates, they’re likely to reject your application outright without leniency. 

My issue is, it's been almost 3 months and I haven't be able to get good tenant applicants.

Challenge is where is their motivation to properly screen applicants and get rid of nonpayers?

The behavior is a bit off, but not surprising for a mom & pop landlord.We tell our residents exactly what we need from them for the application.