There is no definitive answer to how long it takes to receive a return and you may never earn any return. You may end up holding shares in a company for a long time, but that is not necessarily a bad thing.
When investing through truCrowd, under Reg. CF you receive a security/securities in the business. You might receive a traditional ROI when/if the company is listed on a stock exchange, gets sold, or pays a dividend.
If the company is acquired or goes public you can sell your security.