First you have to specify what kind or work you will do on this Laptop you planning to buy to know what specifications you need on this laptop.
Now I will tell you about the main specifications on laptop that effects the cost
1- Processor – it the device that responsible on processing tasks
2- Ram – it is the device that responsible on storing the running programs
3- Hard-disk – it is the device that responsible on storing the Data, like programs documents moveis etc.. all kind of data will be stored in on the hardisk.
4- VGA – Graphic card, it is the device that responsible on the store and display graphics on the screen and dont care to this device if you are not a gamer or a graphice designer.
also you need to choose which screen size you like and which size fits your work, don’t forget the screen size will effect the size of the laptop, so you have to decide what laptop screen size is better for you, if you always using desk when you work, you don’t always moves with your laptop and you like big screen, in this case 16-17 inch will be suitable for you,
other wise if you always moves with your laptop, you like to working in cafe, you don’t care to screen size and you plannig to buy a nice bag for your laptop then your choice will be 13 inch or even 12 inch, if you are confused with this option choose 15 inch if you tend to bigger and 14 if you tend to smaller.
Don’t forget to have a look at your the laptops of your friends and colleagues to determing what size is better for you.
Return to the specifications, ّI would like to mention to the operation system, if you are not familer with any operation system like Windows or macintosh which will effect your decision, in this case I strongly recomend Apple laptops which operating on macintosh.
below some deals based on the work kind