While a western WA deal might not meet some Midwest cf metric like 1%, it will be above the market cap rate or below FMV of comparibles and give you options. 

In many markets section 8 is higher than market rate. and investors need that extra return to mitigate the risk of sec 8 tenants generally speaking.

In San Diego at the current rates for a purchase loan (which has better rates than an ADU additions) at high LTV, I show 1% does not cash flow on a sustained basis.  

Maintenance and potential repairs will also require a long-term financial plan and setting aside a contingency fund for such expenses.The steady cash flow, appreciation over time, and tax benefits can make a meaningful difference to your wealth in the long term, especially with the principal paydown on the mortgage.However, if managing the property from a distance feels too burdensome, or if you’d prefer the certainty and flexibility that comes with having less debt (especially given the high mortgage rates), selling and using the $100,000 in equity to reduce your loan for your next home may be the smarter move.

Right now, you have a property with a great equity position, solid cash flow, and cheap debt (interest rate is low). 

Quote from @Kaushik Sarkar: I’m exploring strategies to scale my real estate portfolio given the current mortgage rate Not sure much makes sense at 11%...Ouch....tough enough at 7.5%   Might have to put more than 20% down to finance....maybe 30% in North Texas.   

They could self manage for several years, using the rental income, until the next phase of their retirement.If they have a decent amount of financial discipline, they may want to get a HELOC now before they build to get the most favorable rate.

Are there tenants looking for mobile homes to rent, and what are the going rates?

I'm not sure if they still have that in this current rate environment but they do exist. 

For the most part, due to interest rates, breaking the 1% cap rate still won't provide positive return after expenses.