Hi Kichara and welcome to the forum.
Which vape to buy is a question that comes up often. And the answer isn't that easy. It depends on a variety of things; specific needs and price point being two of them. If you are going to be using this vape for mostly personal use, two that I use and would recommend are the Magic Flight Launch Box or the Myrtlezap. The LB is a portable vape and will run you around $100 shipped, depending on where you live and where you buy it from. I would suggest reading that thread for more info:
http://www.fuckcombustion.com/viewtopic.php?id=909
The Myrtlezap, while not as portable, is another nice vape. It will cost a bit more, starting at $145 shipped. That thread is here:
http://www.fuckcombustion.com/viewtopic.php?id=1008
I know it seems like a lot of reading, but since you are on a fixed income and price is important, the more educated about the product you are, the easier it will be to make a choice. There are several other types of vapes out there that might suit your needs better, including some with whips or bags. Until you determine what you want from a vape, you can't really make that decision. Take a little time to do your homework, read about several different types of vapes here on the forum, and I think you will be happier with your purchase.
Good luck!