We have a client who agreed to pay $110 for a website he wanted us to design and after we developed site for him he really liked the website now when it is about making payment he is trying to create issues that do such and such extra thing to get payment. I doubt even after making payment to our paypal he can't be trusted. How to safeguard myself on that?
$110 for web design? Sounds like a low quote.
That said, the only way to protect yourself is to curate proof of work done, conversations, even logs of hours spent on his project. Ensure that you send him a detailed invoice (you can use one of the online invoicing services--I use Hiveage).
You'd need these to contest a dispute, should the client take that route.
However, I should warn that doing all these does not guarantee that your client wouldn't be able to get back his money successfully if he means to. If he makes payment using a credit card, he could file a charge back through the credit card company. And things can go sideways quickly if he does that.
Firstly, PayPal would reopen whatever dispute relating to the transaction is question, regardless of it is was decided in the seller's favor. Secondly, winning a CC charge back is very difficult compared to PP disputes.
PayPal is great if you aren't dealing with douche bags. But if you suspect this client might be one waiting for the right time to pounce, you may be best served to accept payment using another payment processor (say Bitcoin).
Nonetheless, some clients can be fickle. It does not necessarily mean they are scheming to make you deliver a free service.