How does warehousing work?

Best practice for warehousing is: i) you invest in a company on behalf of your fund or you invest in a company through an entity that you wholly own on behalf of your fund; ii) when the fund holds its first close and receives LP contributions, you or your hold co transfers the warehoused investment to the fund at cost; iii) the fund either purchases the interest or you treat it as a contribution to the fund. In terms of timing of the transfer, best practice is to do it as soon as possible after the first close.

Warehoused deals are a great way to have an immediate markup and provide incentive for LPs to invest.
You will need to set up a consistent rule for transferring warehoused deals - like "all seed deals in the fund thesis made in the last 12 months", you can't pick and choose deals to transfer in.