I suppose it depends what a person considers expensive. Considering I have no sewing/sculpting background I buy my cosplays and modify things that I feel confident I can do where possible. My first cosplay ended up costing around the $125 range and I slowed added to it over the coarse of time so there's probably about $200+ rolled up into it.
Anime Detour 2015:
• Cat Mask Spider Splicer [40% Complete]
•New Batman Returns Catwoman [30% Complete]