I spent about 8 dollars on my antenna delete- if I only used the plasti-dip for that, and never used the extra washers (why can't they sell a one pack?!?!).
The improvement
probably couldn't be calculated in a wind tunnel lol
But as you said it might be a hobby...it is one for me! I don't spend money on alcohol- so what some friends spend in a night can pay for a 4x10 aluminum sheet