With only 7 to 800 taps I would buy one of the smaller ones with fewer plates and sections. I would think with that tap count you will be looking at 15 to 20 gallons per day. So there is no sense in purchasing one that will do a lot more than that. Not saying you can't remove sections and plates and use a spacer to use it for smaller batches, just that unless you see yourself expanding in the future stay with a small one. I think Leader makes one of the plastic ones with 5 plates and know you can get a small aluminum one.
Then comes the decision as to whether you go with an air pump or gear pump
Good luck
Keith