The best reflectors are often the simplest, the classic 4'x4' bead board from Lightbulb Rentals has a white side and silver side.
Telescoping Stirrup w/ Pipe Clamp 3′-6′$6/day
Black Pipe- Threaded Coupler, 1-1/2″$14/day
C-Clamp: 6″ (Studded Baby Pin)$3/day
Square Frame: Corner (3/4″)$3/day
Pipe Clamp: Baby Male$5/day
Parallel Double Pipe Brace (1-1/4″)$7/day
Heavy-Duty Adjustable Background Crossbar (4.8′ to 13′)$7/day
Apple Box: Half$4/day