alisalem on "Only Admins and the post author can view a post, is it possible?"

Hello,

I have a site where my clients click on New Order icon then fill up some form (jquery) and this order will be consider as a post so the orders look like this:

http://www.mysite.com/order-1
http://www.mysite.com/order-2
http://www.mysite.com/order-3
http://www.mysite.com/order-3

Now, everyone could see the order details by pasting the links above in their browsers. I want to restrict the post visibility to admins and the client only, I know there's a way to keep posts password restricted by a password, but I wonder if it's possible to have only the admin and logged in client see his/her order for example :
http://www.mysite.com/order-2

I try to find an available plug in but I could not find any. my question is, is it difficult t make? and how much it would usually cost to make a customized plug in like that.

Thanks
A