Note 1 - Organization and Basis of Presentation (Details Textual)	12 Months Ended
Dec. 31, 2023 USD ($) ft²	Dec. 31, 2022 USD ($) ft²
Number of Limited Liability Companies	2
Number of Limited Partnerships in which Company is Sole General Partner	5
Long-Term Debt, Maturity, Year One	$ 23,491,706
Number of Reportable Segments	3
Restricted Cash	$ 3,700,000	$ 4,400,000
Customer Concentration Risk [Member] \| Rental Income [Member]
Number of Tenants	1	1
Customer Concentration Risk [Member] \| Rental Income [Member] \| One Tenant [Member]
Concentration Risk, Percentage	6.43%	8.57%
Mortgage Notes [Member]
Long-Term Debt, Maturity, Year One	$ 23,500,000
Model Home Properties [Member]
Number of Limited Partnerships in which Company is Sole General Partner	6
Commercial Property [Member]
Number of Real Estate Properties, Fee Simple	12
Commercial Property [Member] \| Partially Owned Properties [Member]
Number of Real Estate Properties, Fee Simple	2
Model Home Properties [Member] \| Mortgage Notes [Member]
Long-Term Debt, Maturity, Year One	$ 13,100,000
Shea Center II [Member]
Restricted Cash	$ 1,100,000	$ 1,100,000
Area of Real Estate Property (Square Foot) \| ft²	45,535	45,535

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Represents the number of limited partnerships in which the Company is the sole general partner.

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Represents the number of tenants.

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Area of a real estate property.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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The number of real estate properties owned as of the statement of financial position to which the entity has fee simple title.

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No definition available.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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