How have you structured pre-holdco / pre-search-fund capital?

Question for holdco, search fund, and acquisition platform operators. For those who have raised capital before the long-term capital structure was finalized: How have you structured pre-holdco / pre-search-fund capital? I've come across three approaches: 1. Selling a small percentage of future GP economics. 2. Giving early supporters preferential access/allocation into the eventual holdco round. 3. Using some form of convertible instrument that later converts into the holdco/search-fund structure. Has anyone here actually done one of these? Which structure worked best in practice? I'd especially appreciate hearing from people who have raised or invested in acquisition platforms, holdcos, or multi-acquisition search models. Feel free to comment or DM.