Given your limited budget I'd suggest the following.
Two lengths of 1.5" steel pipe, beam clamps, 3/8" threaded rod and pipe hangers. This will give you two 21' long lighting positions for around $ 150.00
Keeping things simple, 8 - Puck
RGBAW Pars around $ 1432.00, 4 - Puck
RGB Pars around $ 400.00, 1 - Magic 260
DMX controller at $ 599.00 around and clamps,
dmx cables and
safety cables for about $ 250.00 puts you around $ 2800.00.
I just did an installation at a Boys & Girls Club almost exactly like above with excellent results.
Here's a shot taken during the
first rehearsal using lights (not bad for the board op who had never done lighting and was new to
DMX and color mixing.)
During the installation my grandson Ty was checking out Papa's work.