Question on Distilate quality for vape pens, are there different grades etc? What is good pricing for a quality liter l today.

Looking to get into making vapes with disty and terps, just want them to be clean/quality. I was going for rosin at first and people would rather just dab it with the super high quality and prices its not worth putting it in pens. A lot of people want the economy and convenience of a vape pen without worrying about tons of chemicals / harsh smoke. Always done everything in-house but will def not be making distillate anytime soon so its all new to me. Also curious to what the best pens disposable or re-usable for disty are.