Vampires are often changed from media to media, but there're a few rules that literally cannot be changed or else your vampires are stupid/weirdly kid friendly
Vampires must be hurt by sunlight. Usually, this is instantly disintegrating into ash. Other times, it's like sticking your arm into a fire 4 times as hot as a normal one, but not instant. Sometimes, only the part that gets hit will be damaged, not the whole body. Rarely, it will just be extremely painful, but not lethal. No matter what though, sunlight must be excruciating.
Vampires must have heightened bodies. Not every sense has to be heightened, but they do need to be. Smell is mandatory, their vision has to at least be better in darkness, but it's the writer's choice if they have better hearing. Along with this, they have to be faster and/or stronger.
Vampires must feed, and only human will suffice. Vampires are carnivores. They're made to eat human meat. We are vampire's natural prey. Vampires can survive off of other meat, but it's a bit like eating fake meat for us: not a perfect substitute. Vampires can eat vegetation, but it's a bit like eating chocolate for us: edible, but nutritionally useless.
I've found that if your vampires follow these rules, no one will complain with your own creative choices, like if crosses, stakes, or garlic are anything special, or if they can turn into bats or enter homes without asking. Of course, if you're making something for little kids, you can probably throw 1 and 3 out, but know that it will be OBVIOUSLY kid friendly, to the point of being obnoxious to older audiences if you're not careful (see Adventure Time as an example of what to do)
