SUBSEQUENT EVENTS (Details) - USD ($)						1 Months Ended		3 Months Ended		12 Months Ended
	Mar. 09, 2020	Feb. 29, 2020	Jan. 31, 2020	Jan. 06, 2020	Jan. 02, 2020	Feb. 29, 2020	Jan. 31, 2020	Mar. 31, 2020	Mar. 30, 2020	Dec. 31, 2019	Dec. 31, 2018	Apr. 30, 2020	Mar. 27, 2020	Mar. 02, 2020	Feb. 01, 2020	Jan. 24, 2020	Jan. 14, 2019	Jan. 19, 2018
Subsequent Event [Line Items]
Payment for tenant improvements										$ 3,486,927	$ 0
Proceeds from issuance of common stock and investor deposits										34,555,691	44,223,885
Dividends										$ 10,585,519	8,281,817
Stock repurchase program, shares authorized (in shares)										2,376,509
Repurchases of common stock										$ 12,145,903	$ 8,688,479
Subsequent Event
Subsequent Event [Line Items]
Distributions declared per share per day (in usd per share)			$ 0.0019221				$ 0.0019221									$ 0.00191257
Dividends						$ 1,382,532	$ 1,391,612
Stock repurchase program, authorized amount													$ 17,820,513
Repurchases of common stock								$ 9,091,146
Common Class C | Subsequent Event
Subsequent Event [Line Items]
Stock repurchase program, shares authorized (in shares)													1,737,191
Repurchases of common stock (in shares)									895,216
Common Class S
Subsequent Event [Line Items]
Net asset value (in usd per share)																	$ 10.16	$ 10.05
Common Class S | Subsequent Event
Subsequent Event [Line Items]
Common stock issued in transaction (in shares)		187,295
Proceeds from issuance of common stock and investor deposits		$ 1,900,868
Stock repurchase program, shares authorized (in shares)													3,309
Repurchases of common stock (in shares)									0
Net asset value (in usd per share)			$ 10.16				$ 10.16								$ 10.27
Distribution Reinvestment Plan | Subsequent Event
Subsequent Event [Line Items]
Dividends						851,331	$ 830,660
Distribution Reinvestment Plan | Common Class C | Subsequent Event
Subsequent Event [Line Items]
Common stock issued in transaction (in shares)		1,673,199
Proceeds from issuance of common stock and investor deposits		$ 16,893,207
Distribution Reinvestment Plan | Common Class S | Subsequent Event
Subsequent Event [Line Items]
Common stock issued in transaction (in shares)		2,982
Proceeds from issuance of common stock and investor deposits		$ 30,318
Short-term Notes Payable | Subsequent Event
Subsequent Event [Line Items]
Debt instrument, interest rate, stated percentage														8.00%
Short-term Notes Payable | Chevron Gas Station, Roseville | Subsequent Event
Subsequent Event [Line Items]
Face value														$ 2,000,000
Short-term Notes Payable | Chevron Gas Station, San Jose | Subsequent Event
Subsequent Event [Line Items]
Face value														$ 2,000,000
Convertible Notes Payable
Subsequent Event [Line Items]
Face value										$ 4,800,000
Debt instrument, interest rate, stated percentage										8.00%
Aggregate fair value										$ 1,242,233
Notes payable extension fee percentage										2.00%
Notes payable extension fee										$ 24,845
Convertible Notes Payable | Subsequent Event
Subsequent Event [Line Items]
Debt instrument, interest rate, stated percentage												10.00%	10.00%
Notes payable extension fee percentage	2.00%
Notes payable extension fee	$ 24,845
Maximum | Subsequent Event
Subsequent Event [Line Items]
Gross offering proceeds, percentage			3.00%
Retail | Walgreens, Santa Maria | Subsequent Event
Subsequent Event [Line Items]
Payment for tenant improvements				$ 490,000
Office | Accredo Health | Subsequent Event
Subsequent Event [Line Items]
Leasing commission paid						$ 215,713
Registered Offering | Common Class C | Subsequent Event
Subsequent Event [Line Items]
Common stock issued in transaction (in shares)		18,517,936
Proceeds from issuance of common stock and investor deposits		$ 186,123,756
North Capital | Follow-on Offering | Subsequent Event
Subsequent Event [Line Items]
Sale of stock, dealer, service fees					$ 12,000
Sale of stock, dealer, monthly variable fees, percentage of common stock purchase price					0.60%
Sale of stock, dealer, aggregate gross proceeds, threshold one					$ 25,000,000
Sale of stock, dealer, monthly variable fees, percentage of common stock purchase price, threshold two					0.50%
Sale of stock, dealer, aggregate gross proceeds, threshold two					$ 75,000,000
Sale of stock, dealer, payment of monthly retainer					60,000
Sale of stock, dealer, maximum retainer					$ 180,000