I know nothing about that stuff but hear it mentioned all the time.

Unless a MH is put on a permanent foundation on an actual privatley owned lot, the majority of mobile homes depreciate in value over time.As @Greg Scott mentioned, you can find cashflowing deals if you know HOW to look.

But maybe your tenant reaching out and mentioning that they're going to be forced to file a police report for fraud could generate some traction...obviously the real objective here is to just get the seller to call you back...

Which reminds me that I should mention that I’m not opposed to living a not-so-luxurious lifestyle in the short run.

prices are high, interest rates are high, there is tremendous demand for inventory, and - one thing that doesn't get mentioned enough - a record number of properties are debt free. 

As mentioned 90 day limit, which makes it difficult, and wuite pricy to get the STR certificate from the city. 

The location all in,cost him X; he got an appraisal for the bank from CBRE national firmof XX and now the firm who called him mentioned paying XXX.

A few of them also mentioned that they don't really expect this to affect the housing affordability in the county, but do believe that STRs can affect the quality and integrity of the neighborhoods in the county which they want to preserve.  

Like the others mentioned, either 3.5% down if you intend to live in it.

Either way if it helps someone out especially going through what he mentioned it may add some gratitude and help him avoid further late bills.You can get more bee's with honey so in some cases it can pay off being a little more lenient.