I am a software engineer looking for short-term employment and/or work on a for-hire basis (for a number of reasons - I know I'll have other commitments in 2017-18).
Now - there is this guy, who got my contact through a mutual acquaintance, who claims to be "in the process of" launching his own startup.
We exchanged a few mails in which he explained me his vision and a vague idea of the business plan and asked me (without further details) if I'd be interested in doing "engineering work".
I said "yes, sure" and asked for further details.
It turns out that there is nothing in place yet (except a simple homemade website) and his startup (or startup to be?) doesn't have a CTO.
So, I answered something along the lines "yes, please call me when you are ready to start and we'll set up a meeting and maybe do a study, define some requirements and see what we can do".
Now he's taking to texting me on WhatsApp (which I never suggested was an option) because "he doesn't like email", which I am not okay with.
I like to do business through email, phone calls and face-to-face meetings, I don't like receiving vague messages and "hi"s at 1AM on my phone.
I am not pleased with the direction this thing is going.
I am worried that no actual work will come out of this at worst and that this person will make me rather miserable at best.
What are some strategies to make this clearer and more professional without jeopardizing the relationship?