New times bring us new methods. Sometimes vampires were staked and burned. Today if we want to slay a beast we have a lot more methods to do that. Shotgun in the face is something that nobody likes to see. Even a vampire shot from close range with load of whitethorn thorns or a small stake would not definitely be happy about it. And if you are great shooter you can easily shot him in a heart with whitethorn pellets. And if you miss, you always have another round. If you are a sharpshooter then even a crossbow could do the job or even a bow, but if you are not shotgun with whitethorn pellets would be my chosen weapon. As you can imagine there are a lot of possibilities and we are limited just with our imagination.
I might be wrong but the flamethrower is practically legal almost in any part of the world. Even if it isn’t, you can still make it easily with a can of deodorant in pressured bottle. Or even make a garlic deodorant which would be a bit more expensive and not so easy to make, but still… Yet again only our imagination is the limit. Something like garlic pressured bottle with flame in front. Double purpose weapon…
Some author’s state that silver can be lethal to vampires. It is a bit complicated to explain this but let me try. Vampires in Serbian folklore can change to werewolves and they occasionally do that. When they do take this form silver will be effective. Nobody knows why, but that’s the case in folktales. On the other hand if they are in their regular – dead body form that will not be the case. Even so, that would be pretty expensive way to kill the vampire. My suggestion would be to use flamethrower. Inexpensive, easy to build, easy to use and you would probably have most fun doing it. But if you are a gun nut, that bring a whole lot different experience.