Um, yeah... The Lost Warehouse is no place to play with "good decks", i.e. "to win". It is possible, sure... and it will make lots of people really (and righteously) angry at you. The Lost Warehouse serves to get XP for your cards, not to play to win. Nobody serious tries that there. It is no achievement. If you try to "win" there, it only shows that you have either not understood its purpose or that you are a total jerk and think yourself great wonning against people who do not try to win themselves (but to optimise the XP gain for their cards, in most places.)
For deck ideas, I suggest http://kirlad.no-ip.com/juegos/urban-rivals/elo.php ... You'll probably need to replace some expensive cards with cheaper (and worse) ones that are similar.
Well it depends on the deck you want to make, i would honestly buy Samantha, Zatman, Rubie, Striker, Flo, Marina, and Alexei for a fresh start , but if you have a Lamar, don't bother with buying Alexei and since you have bought credits, try to market Gina Glitt *2, by doing this you have a Tier 1 deck with little upkeep (buyinh 2 Gina glitt at 28 stars around 800 clintz per week upkeep).
Well these are the cards i have at the moment
sorry i dont know how to link should i keep any of these?
Sai San 2/4*
Xia Leming 3/3*