your best bet (this is what i did) is to go online to places like home depo and lowes and visit cheap places like dollar stores and such, and start a list of items that are the same in the starter kit, but not reptile brand (alot of reptile brand stuff is the same exact stuff, but overpriced).
i know for a fact lowes has a pressure spray bottle, dome lamp, tube light fixture, appliance timer, plants (my ultimate favorite is pothos) and some other useful things. you can make a dripper out of a gallon jug with a hole poked in it you really only need a plant or two for a single cage and some dial rods or branches and some fake vines (michaels arts and crafts, about $3 a 5 foot vine) a housebulb for heat and a uvb light (about $17 on josh's frogs compared to the $30 at my local petco). so you really just have to look around, im sure you could come up with a setup 10 x better than that one for a better price

also, check the classifieds here, there are tons of great deals on used cages! except for your cham, they are the most expensive part of the setup..so i suggest buying used, you could get a great cage for about $30-$50 here..and new ones are anywhere from $70-$100's.