When looking for a Truck Rack for your vehicle there are a couple of considerations to think about.
Price
You have a budget to work from so this is going to limit your range of choices first up. Racks can range from about $30 right up to over $1000 for some of the more Commercial Racks
Usage
Normally there will be a specific task that your Racks will be used for - My advice is simple, buy the best Truck Rack that you can afford that will do the job. A decent Truck Rack can last a long time, so there is no point in just buying the cheapest.