Typical Co-investor Equity Terms? (Self funded)

Trying to get color on co-investor equity structure and terms for a self funded search where the searcher is investing capital in the deal and also raising outside capital. Does anyone have a sample term sheet or summary of basic equity structure and terms for co-investors coming in at acquisition for a self funded search? I understand co-investors are typically investing in preferred stock with a dividend; is there typically also a liquidation preference? I have seen a few deals where outside of the management common stock that vests, the co-investors buy in at a higher valuation than the enterprise value of the deal (i.e., get a lower ownership % for their $) so that the searcher gets a higher % of the preferred equity for their invested dollars. Can anyone point me in the right direction of how to think about these items? Thanks!