Gargoyle geckos are probably easier to care for than corns in a dorm, and WILL stay at a manageable size, while some corns may get a bit bigger than you want.
Let me start out by saying that the corns in Petco may have been stressed, or the producer sold them to Petco instead of individuals because they are/were "hatelings", aggressive or overly frightened hatchlings.
With heating, you'd need to get a heating pad and thermo/reo-stat to regulate for a corn, while gargoyles do fine with no heating or cooling as long as it stays around 65F to 78F.
Gargoyles will also eat food that comes in a jar. Just add water (or don't xD). Around 8 dollars for 50 grams (1.75 ounces) of Repashy Crested Gecko Diet at Petco. That should last a really long time since babies eat very little, and adults only need feeding every 2 nights or so, but also don't eat very much.
A 10 gallon or 20 gallon long tank is plenty big for one adult. Since gargoyle geckos, probably around 80% of the ones I've checked out, are horrible climbers and generally live at the base of trees in the wild, they'll enjoy more floor space than height and need rough climbing branches (as opposed to many other geckos sticking upside down on glass XD).
My 30 gram or so gargoyle is like a puppy dog, somewhat. She's very calm, likes to hide in my robe, explore when she gets the chance.
Just about all care sheets are good. PangeaReptile has a great one on cresties and gargoyles, since their care is just about identical.
IMO you can't go wrong with a corn or a gargoyle gecko.