Have you tried vaping, yet, if you have, did you enjoy, mouth to lung, or direct lung?
The way you prefer to vape, makes a huge difference in which TOP device, the MOD portion, not so much. A quality MOD, on the bottom, will work with MOST top devices, whether tanks, RBDA, or others. Most people, start out as mouth to lung vapers, as this most closely mimics smoking. Some stay mouth to lung for the flavor. Others migrate to direct lung for the clouds. Some do some of both. For a great mouth to lung experience on a tight budget I would suggest an AIO. Direct lung, I recommend an RX 200 or RX200S with a Tobeco Super Tank 25mm. You will need some 18650 batteries and a charger is a necessity too. E-liquid also, and some spare coils. The AIO comes with, enough to get you started, except e-liquid. The other option requires you to buy things in a more piece meal way.
Most vape shops charge considerably more, than the online vendors do, so try, face to face, perhaps, but price and buy online. There are lots of great resources here on the forums, about which sites, others suggest. I used to spend $58 a carton, per week when I smoked, I do not spend on average more on vape gear, but the initial costs, can be a high buy in cost for quality products. Thankfully the price is much lower than it was when I started three and a half years ago.
Welcome to the forums, and I hope you find a setup you enjoy using, easily, and within your budget.