Me personally, I don't pick up a pencil, mouse, turn on a computer, put on my glasses, etc..... nothing unless a fee has been determined for the work I'll be doing.
In some cases, a deposit may be required before I start work.
Imagine... you put in 10+ hours of work and then the client says something like, "Well, we thought $15/hr was a good price." Or even less. That's minimum wage in most areas of the US now. So they want to use you for your technical expertise, but pay you as if you were any random person off the street??
Overcoming such lowballing is very difficult after you've done the work. I mean, if they simply won't pay more, you can refuse to provide anything and you've done all that work for nothing. Or, you succumb to their lowballing and the client has (happily) conned you into working for mush less than your regular rates. In many cases, the client is fully aware that after you've done the work you are more likely to accept lower-than-normal payment just to get any return on your efforts. It's a "con" a "scam". Discuss pricing before starting work.
A new client, even someone I've known but have never worked for as a freelancer, asking me to work before discussing price would honestly make me chuckle, not to their face, but that's how ludicrous the proposition is to me. In fact, it's so ludicrous that I'd demand a non-refundable deposit before any work began. Primarily because such a proposition, to me, is seen as a "red flag". Meaning, clients proposing such a thing will typically be slow to pay, and will do their level best to lowball any pricing or get discounts, etc after negotiations. The deposit generally ensures I at least make enough to cover the initial stages of my work - clients sending up this flag for me will generally become less interested or involved after initial stages. Or they go the other way and start becoming overly demanding, try to balloon the initial scope, etc.
Essentially, they've sent me a warning that they may be a "difficult" client in some way. A deposit merely means if they do become difficult, at least I'll get some return before the wheels possibly fall off.
If the red flag was a legitimate warning, they'll argue about the deposit - if they argue adamantly about it, I generally turn down the work. If they won't pay the deposit, I'll have trouble getting paid after completion of the work.
On the other hand, if they are legitimate in their intention to pay or simply have enough money that price is really no object (which can happen), they won't have an issue paying a deposit. They may need some reassurance that I'm not going to merely take their money and disappear, but it's not the actual financial hit which concerns them.
(Experience and longevity in the profession tends to dissuade the notion that I'll disappear.
That was more an issue when I started than it is now.)
So.. to this employer, I'd reply:
"Sorry. That's not how it works. I'm very eager to create a dashboard for you. However, we need to determine the project fees before I start work. In addition, there will be a non-refundable deposit required before work begins. I won't simply start work with some unknown return looming at the end of all my efforts. I need to know if the return on the project is worth my time."
Just a personal note: Working for past employers can be tricky. I've done it. The initial relationship was established under specific circumstances. One where they had domain over you and what you did and to that end, felt in control of everything, as they should have at that time.
Once the relationship changes to more level ground, as in Freelancer <> Client, they may not move on from that established mindset. It can often take quite a while and some direct effort on your part (as in pushing back when they are overstepping) to move past their notion of control. Remember this is your business and you control it. You are not obligated to put your own needs and desires aside merely because they want you to.