Depends on who you are talking to. Many small companies and startups won't pay anything for a strategy. They can't. They pay for work and for results.
So be careful about over valuing a plan and under valuing execution. The former is easy, the latter is time consuming and usually what clients are far more interested in.
We talk through a client's needs and priorities, then we start with a simple, short engagement. We call it "dating before getting married." The idea is that we'll learn so much more about each other in 3-6 weeks than we will in a negotiations process.
We start with a pain point, we solve it. Then we move on to the next. The strategy evolves out of the work, and is far more value added after we've been immersed for a time in the actual data.
My philosophy is that too much time is wasted in conference rooms planning not to fail when it should be about putting things into the marketplace and learning from experience and data.
Clients who don't want that are not likely to be a fit for us.
So, do your best. Be yourself. Keep trying new things with each negotiation and you'll learn as you go. And track your time. You'll be amazed at how you have no idea how much time it takes but over time you'll get good, really good at it and that will make estimates more accurate. It will also help you identify which tasks deserve investment in automation or which should be delegated to lower cost resources.