If you are inspired and love to save money and work with your hands, there are some fantastic decor you can invent for Halloween that will satisfy! Here's a lot of possibilities - 

paper maiche (newspaper strips, mod podge or glue/water mix), string, balloons

carved apple heads soaked in lemon juice and salt, dried in low-temperature oven

cheesecloth, balloon

string lights, doll heads without eyes

doll heads, candles

mod podge

Elmer's glue

glue gun

twine

ribbon

balloons 

glow sticks

cheesecloth

autumn leaves ironed with wax paper to preserve

twigs

acorns

pine cones

moss

gourds and pumpkins

corn stalks (corn dollies!)

hay bales

black cloth

white sheets (cover furniture)

candles

burlap 

Enjoy the season and any reason to craft with what is handy and around you. For example, one post-apocalyptic graveyard themed Halloween party I had, I had old wooden lattices for the garden that were falling apart. I took them apart and pounded them into creosses, painted them with fluorescent paint, stuck them in the ground and shined a black light on them. 

Remember, too, one simple bag of rubber cockroaches can really create a strong effect in a bathroom or kitchen.