Loans Payable - Interest accrued and accumulated amortization of capitalized issuance costs (Details) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Accrued interest	$ 257,375	$ 219,476
Accumulated amortization of capitalized issuance costs	768,354	637,688
Amortization and preferred stock dividends on mandatorily redeemable preferred stock
Debt Instrument [Line Items]
Accrued interest	70,004	70,004
Accumulated amortization of capitalized issuance costs	475,785	366,758
Franklin Square Property
Debt Instrument [Line Items]
Accrued interest	42,046
Accumulated amortization of capitalized issuance costs	16,550	2,364
Hanover Square Property
Debt Instrument [Line Items]
Accrued interest	35,443	38,287
Accumulated amortization of capitalized issuance costs	53,435	46,990
Ashley Plaza Property
Debt Instrument [Line Items]
Accrued interest	34,493
Accumulated amortization of capitalized issuance costs	49,394	40,679
Clemson Best Western Property
Debt Instrument [Line Items]
Accrued interest	46,177	47,716
Accumulated amortization of capitalized issuance costs	134,622	134,622
Brookfield Center Property.
Debt Instrument [Line Items]
Accrued interest	15,321	15,979
Accumulated amortization of capitalized issuance costs	31,217	25,542
Lancer Center Property
Debt Instrument [Line Items]
Accrued interest		22,042
Accumulated amortization of capitalized issuance costs		17,971
Greenbrier Business Center Property
Debt Instrument [Line Items]
Accrued interest		15,482
Accumulated amortization of capitalized issuance costs		924
Parkway Center
Debt Instrument [Line Items]
Accrued interest	13,891	9,966
Accumulated amortization of capitalized issuance costs	$ 7,351	$ 1,838