wishful thinking.
you can get a belt drive bt30 spindle under $1000us. then you need a motor, pulley, belt, drive, tool release mechanism, air regulation and solenoid systems, wiring, mounting block/plates/adapters etc. probably north of $3000 by the time youve got it running.
for internal motor spindles, its usually more. $4000 min all in - even for cheap chinese ones.