Thoughts on M&A

M&A work often requires significant input from Finance, from the original evaluation and modelling, due diligence, financing the operation and adjusting internal structures to the new requirements (cashflow, reporting to investors, adapting to corporate needs in post-acquisition integration…).
Not all of this can be met with internal resources or “usual” partners (Banks & M&A firms), the latter particularly in operational considerations, where a “hands on” approach is needed. What are your thoughts on it?