If you just want to make it look like a low budget ugly bike, just buy some rattle cans and paint it fully assembled. And don’t use masking tape.
Pick a color, or two, you really like and use silver, or better yet gold, for the components and chain. Get some cardboard to shield the overspray.
Of course, you should at least ride it to make sure you like it before reducing the resale value to zero.
John