Selecting the right harness should be less about your budget and more about the safety, suitability and fitment. 

Don’t be fooled by the all singing all dancing, bells and whistles, very often they add little or no technical advantage.

There are, of course, times when side D-rings, belts, abseil points and additional leg supports or padding are advantageous but for the basic working at height tasks a simple two-point product is normally sufficient. Unless a harness is being used where there will never be a need to remotely rescue the user we would always recommend a two-point harness as a minimum.  It adds very little cost but ensures, in the event of an emergency rescue where the rear d-ring is not accessible, the rescuer can safely connect to the casualty.