My brother just recently bought DG, and asked me if there was a way to get both, vamp lord and a xbow. I wasn't sure as I play on ps3. So I thought I'd ask you guys. All replys are greatly appreciated.

The DG give you an xbow before you even have the option to join the vamps. Not to mention you'll be attacked by groups of DG, who often carry them. The only xbows you don't get are the upgraded one and the dwarven ones.

Even if you happened to have ditched the Crossbow that the DG give you before you explore Dimhollow; the Dawnguard will randomly attack you when out exploring the countryside. Kill them and take their crossbows.

They won't need them anymore.

However, you can't get the Dwarven model or any of the special bolts.

If you want to, you can port your files over to the PC version, then port them back. That gives you access to the console commands.

If Durak approaches you about the Dawnguard, you can pickpocket a crossbow off him right then, like I did!

You can get Vampire lord form even if you side with Dawnguard. You lose out on some vampire lord special rings and amulets, but you get dawnguard followers and some really nice dawnguard weapons.

This,
you can get it either way.

Also, when you first start DG, and go to meet them, explore the castle, it will be the only time you can if you decide to become a vampire lord, and you will find several crossbows, plus bolts, plus axes, plus warhammers and even some armor and a shield laying around the castle.