ADU construction is not 1:1. meaning investing 250k into your property by ADU will likekly not increase your property value by 250k.

Purchase price: $410,000 I bought this property during COVID-19 when everyone was running away from buying rental units.

Hard to say much without seeing the property.

I have owned single family rental properties for several years, but am now faced with a unique problem.  

If you want to stay in your house, then your only option would be to leverage equity which will probably be in the 8-10% interest rate range.Not knowing the entire situation, I think you could consider downsizing and then using the proceeds to buy a 2-4 unit property and start making $40-75K right away with still no debt. 

For example the HA will inspect the property every year to make sure it is up to standards. 

I have been an investor for over a decade and helping other investors (many OOS) buy and sell investment properties here in the Dallas/Ft.

I am based in New Zealand and own 4 properties here, but keen to explore investing in the US. 

I'd keep an eye on ancillary properties that become available. 

Has anyone added extra bedrooms to a multi-family property to increase rental income?