The easiest video to follow on how to make balloon arch without stand. You can choose the color you want.

I used 30 cm helium quality balloons and inflated for 22.5cm.
I used 120 balloons for this. Oh! plus 2 for the base.
60 black balloons and 30 red and green balloons.

Why hire pay someone to do it when you can do it yourself.

Balloon pump and sizer was bought online.