Best for Your Budget
Dover Thrift Editions win the prize for lowest cover price, ranging from just $1.50 to $5. Naturally this means they are going to be low quality with virtually no commentary. Basically, they’re great for a one time read, but not something you want to keep on your shelf.
Signet Classics (Penguin) can run upwards of $10, though this is rare, and they have decent introductions. These mass-market paperbacks are of a higher quality than Dover Thrift Editions and there are approximately 160 more titles to choose from in this collection.