Ask how the fractional leader will make room for the beginning of your engagement, not just how many hours they'll give you each month. If they can't explain what happens between signing and doing useful work, get that clear before agreeing to a start date.
I've made this mistake myself. My fractional practice was primarily sales and marketing, and I was focused on growing it fast. I'd onboard a client, then two days later another client, then two days later another.
As I explained on a recent call, “things are starting to fall apart.” I hadn't given each client the attention they needed.
The missing attention was in the first few weeks. I hadn't given each relationship enough time to establish why I was worth paying on a retained basis.
That's something I'd want to understand as the buyer.
Ask what starting actually means
On that same call, we had to clarify what I meant by onboarding. I wasn't talking about waiting for paperwork. I meant “start doing work for them and make them receive value.”
Use that distinction when you discuss availability. A signed contract and a kickoff meeting can happen without the substantive work moving very far.
Ask the person to walk you through the beginning. What do they need to understand about your business? Which people do they need time with? What decision or piece of work will they take ownership of first? What do they need from you to get there?
Then ask whether their calendar actually allows for it. You don't need private details about their other clients. You do need a credible explanation of how they'll handle the start you've agreed to.
Agree on a start they can support
I wouldn't turn my experience into a rule that someone can only start one client a month. If two clients are ready to start, I'm not going to make one wait four weeks just to space them out. The question is whether we can do the work and give both a good early experience.
For your business, an honest later start may be more useful than an immediate start followed by silence. If the work can't wait, find out who can give it the attention it needs now.
Fractional lets you bring in experienced help without making every engagement a full-time role. But the initial work still needs room on someone's calendar. Agree on what will happen, who will do it and when you'll see the first useful progress.