The stage of the company and type and source of funds will dictate the necessary experience. For many debt offerings, prior fundraising experience isn’t necessary. The more a loan is collateralized with a hard asset or working capital, the more the lender is going to concentrate on asset quality. Strong financial operations and accounting come in handy with asset-based lending. A good controller might make a great candidate in this position. If the loan is cash-flow based, a planning and analysis skill set is valuable.
For earlier stage companies raising equity, the majority of the burden is on the founder and executive team, not the finance team. In my experience, many early-stage firms don’t even consider hiring a CFO until after raising a Series A round. If you are an early-stage company pre-Series A, and are looking for a CFO, prior experience is not as important.
Later stage venture capital raises as well as private equity raises require more sophistication from your CFO. Investment banking, venture capital or private equity experience is a good proxy for a CFO who has fundraising experience. However, just like a strategy- or planning-heavy candidate, nonprevious CFO candidates are the most effective if there is a preexisting strong accounting and financial operation, especially a skilled controller.