If a project is already in progress and the applicant is willing to serve the target population(s) and be bound by the service and use requirements, can construction costs already incurred be reimbursed?

No. Funding may not be used for “reimbursement.” Only those costs that can be associated with completing the project (for example, adding an ADA-compliant walkway, widened doorways, etc.) would be eligible costs, per the Welfare and Institutions Code, Section 5960.15: “An entity shall meet all of the following conditions in order to receive grant funds pursuant to Section 5960.05, to the extent applicable and as required by the department: . . . (b) Expend funds to supplement and not supplant existing funds to construct, acquire, and rehabilitate real estate assets.”