As someone who does contract work for companies in other countries, I highly recommend that you don't do that. This is specifically the kind of thing that will get you kicked out of a country. Once you are kicked out, not only are you very unlikely to every be able to get a visa for that country again (even a tourist visa), but you are unlikely to get a visa anywhere in the world. Countries share this kind of data freely.

Stick strictly to the rules (both in letter and spirit). Living abroad and working on contracts internationally is very, very nice. Being able to travel to the countries where you are doing business so that you can have meetings, meet people, actually negotiate, etc is often a prerequisite for getting the contract. Don't screw over your future self.

I wouldn't. Why would you have paperwork to be in the US for 3 months to 'negotiate a contract'.

Its a serious crime to lie or misrepresent to a Federal DHS Officer

I'm not suggesting lying, I'm suggesting using a broad definition of "negotiating"

yeah, I don't think you've had a lot of interactions with Dept Homeland Security.