There are TONS of ways to save money in this hobby, but IMO a protein skimmer is not one of them.
You get what you pay for. The ONLY exception I've ever seen to this is the Coralife Super, which is "decent for the dollars," but I wouldn't call it a "great" skimmer.... just a "decent" skimmer.
Better, more powerful skimmers using induction, downdraft, or beckett air shredding will pull far more waste out of your water, and all the benefits that this provides are worth the money... again, IMO.