If this property is hard to rent, or is functionally obsolescent (only 1 bathroom, no yard, etc), or has deferred maintenance that will be costly, or is in a location that is not appealing to Tenants, then maybe a sale would be a good option in favor of a property that has better Tenant appeal, which will likely increase rent and avoid long vacancies in between Tenants.An option to consider....

(It could take 8 years to get to today’s market rent, if market rent didn’t increase $1 during those 8 years.  

If you spend time learning how to manage well, your income will increase, you'll save time, and you'll maintain your sanity with the courage to expand.

How much will the increased cashflow supplement your anticipated SSI?

Washer/dryers are often abused, so there's the initial cost of purchase and the risk of increased repairs.

There are some locations to stay away from but almost every single sub market of KC has value and increasing rents.

Remember, investing 200,000 into an ADU won't likely increase your properties value by 200,000, but the rent potential is a great bonus.

In some homes planting the front or placing pots could increase the curb appeal, in others it could be paint or furniture etc.

Quote from @Paul Lucenti: Creative methods tend to increase risk.

That the rent increased?