I've been making jerky for years and the number of friend I have usually increases when words gets out that I mad a batch. I've been told I should sell it at farmers markets but that's to much work. lol
I have made as much as 20-30 pounds in one batch. to be specific, there are normally 3 or 4 different recipes but I can dehydrate them all in one bacth.
When you say professional dehydrator how many pounds of meat are you thinking of dehydrating?
I used the blackndecker models when I first started out. They were terrible. They took 3 -4 times as long and they didn't hold much.
Here is a link to the unit I have.
My unit came with 4 trays and is expandable to 20. I believe I have 20 trays and have never filled them all. My unit is electric and works with a fan and a heat element. It has a thermostat that adjust from 95 degrees up to 155 (or 160 can't remember) degrees. What I do is shift the trays around every hour or 2. Some trays will finish cooking before others. you have to monitor it. I could recommend this unit more. It's 20 years old and still works great.
I hope this helps. please feel free to ask anything you like if you have more questions.
You will love your jerky.