In Spanish, when a word begins with a 'v', it must be pronounced like a /b/. So it should sound like "BEH-stido"
The other way around is true too: when you see a 'b' in a word and it's not the first letter, you pronounce it like a /v/. So do you remember the verb "beber", meaning "to drink"? Yeah it should be pronounced like "beVer".