This will most probably be a hard lesson for you, but one that is needed. Unfortunately you do get people like this, but as time goes on you'll learn, just like I did when I worked for myself. Have everything in writing. No verbal crap.
Be upfront and clear about how and when payment will be made. As for a website, do x-work, get paid. Carry on doing another bit of x-work, get paid.
If they complain about "Why must we always make these payments and why can't we make one big payment", then you tell them you've been burned in the past and it's just to protect both parties.
Back in the day when cheques were accepted I straight up told my clients no cheques. If they asked why I told them I've had bad experiences in the past with cheques that bounce.
Be upfront, yet professional. If this douchebag doesn't pay you then accept it ( after you've done what you can ), and move on. However, learn from this experience as to never repeat the same mistake again.
Remember, this used tampon can hurt you more than you can hurt him. Word of mouth, especially when it's negative, can literally kill a business and bring it down to nothing. I guess that works both ways, but if he gets snotty and starts spreading rumours because you got nasty regarding payment... eish.
Alternatively, and this is a bit of a sneaky way, give their number to someone and have them call the client. Say they're from so and so and calling for payment as it is now past due. If he calls your bluff you're screwed though. :/
As a last resort you could do a redirect on that domain to meatspin.com