12v....which...where?

[wacattack]

As me and Craig have been using a 12v that needs to be on charge all the time as it runs flat after charging about 2 packs of cells from it, I thought it was about time I invested in a new one.

So, any recommendations? Which one, where from, how much?

Want to pay about £80, but willing to budge if you think its needed

Thoughts on a postcard please

Wayne