Should cash flows form future Capex. be included in Future cash flows, while valuing a private company for merger

Hi, I am doing a DCF valuation of private company for a investor, who wants to fund a target requiring funds for future Capital investments.

My query is whether I should value the company based on future cash flows of existing assets or should i include the cash flows from existing as well as new assets which would be created from the funds of new investor?

My view point- free cash flows should only be calculated from existing assets as growth from new Capex should be shared with new investor as well as founder.

Please provide your view points on this . Any additional literature would be appreciated.

Thanks