If I was in a position where I needed to know this, I'd be sure to ask my fellow homeless.
Counted up to 17, but the 17th one was 500ml worth of everything my mates found.
The best way and the cheapest, is to go to a good Polish store and get some mocna strength beer, like Tatra mocne, or Perla mocna. It is cheap but of good quality. 7.5% or thereabouts and is a pound a can round my way. Imported and made properly.
Far better on your tastebuds and far less bad for you than that horrible synthesised 'cider', like Frosty Jacks.
Are you Scottish ?