Private Jeeper Smitty here...need advice on painting...

So my jeep needs some TLC in the painting area.

What do you suggest on undercoatings? Bumpers and hinges...

So far I took the rear bumper off...sanded the rusty areas, bathed it in acetone to get rid of any oils and then shot it from a can of rustx black paint from advanced auto. Probably 3 coats. Flat black.

Can you tell me what you all do? If I wanted more professional job would I buy a compressor and bead blaster hookup? and if so which ones would you recommend?

I just want to protect it as much as possible from the snow and salt of the up coming winter.

Ultimately I want to line-x the underside and interior but that takes major money that I don't have currently.