This is an often asked question and you could probably find your answer doing a search on this site.
With that being said, if you are interested in receiving C Band, a minimum dish size of 7.5 ft. is recommended.
Dishes 7.5 ft. and larger can usually be had for free by combing through Craigslist.
Wildcat, if you want to drive just across the VA line to Cana Va, you can have a 7.5 KTI mesh for free. Dish and mounting ring only. (I am using the old actuator elsewhere).I'll throw in an old lnbs if you want it...but it has never been tested and probably bad. Dish and mounting ring are down and ready to load. Take ya less than 10 minutes to load. Dish will haul in one piece in a small pickup if well tied down.
I'm about 8 miles north of My Airy NC, up Highway 52. About 45 miles north of Winston Salem.
If someone doesn't get this fairly soon I'm going to store the mesh screen and mounting ring for possible future use,, and haul the dish ribs to salvage. I'd prefer it to go to someone who will use it but I have to clean up some of the clutter around the house.