Seen in the wild:
This sign so incensed my sister, she went back and took a picture just for us. See it? It asks, “Have alot of square footage?”
This is a simple one, folks. “Alot” is not a word, unless you are referring to that little town in India.
When talking or writing about a “considerable quantity or extent,” it is correctly written as “a lot,” two words.
If you need further memory aids, as this site humorously points out, “You shouldn’t write ‘alittle’ either.” (At least, I hope he meant it humorously. I can’t say I’ve ever seen “alittle” in writing, but maybe I’ve missed something?)