What is your idea of cheap. Are we talking $20 bucks or $80 bucks. You gotta start with something at least semi satisfying IMO or your going to think that crap you got is all this wonderful hobby has to offer and probably leave it alone. Here is what I would get them:
I Stick 30W-$35-$45
Silo Lite BVC or reg Silo BVC (essentially a better Natilus *IMO*)-$30
Some sample pack from Mt Baker-$30ish depending
its $100 bucks but if you love these people I think you should start em off with something that will make the "this is BETTER then ciggies" lightbulb go off
I know you said as cheap as possible but you really do get what you pay for and I am sure there will be hoards of $7 egos being posted but I don't think that will draw them in enough and I think they will just go back. Also your finances play a big role in what you can do I just think this stuff isn't a game it can save lives so why start with such junk. You don't need a DNA 4O n a RDA I just think with the advancements you should go middle of the road specially if its for your mom or someone you love and please read my story below so you know why I feel this way,
I tried and tried to get my dad vapeing cause hes going to die from complications of smoking unless he stopped. I spent tons and tons of money (my dads poor, alcoholic, social services etc and I sell commercial real estate..nuff said) and nothing was working. I said screw it and told him if he allowed me to teach him just basic battery safety I would do everything else (coils etc) for him and give him two bottles of black label. I taught him about batteries, I gave him my original Sig 100W and a Darkhorse. He hasn't smoked since and comes by every Friday so I can do what needs to be done to his gear. I think the other stuff wasn't satisfying him, huge 12mg lung hits really do though lol. My point is if your trying to save someones health the cheapest gear might not be the best but I understand not everyone makes 100+ a year so do what you got to do I just wanted to share my story. And I don't want to sound pretentious either. If my grumpy old man is around even one extra year the $3142.47 and two years I spent trying to find something he loves was well worth it, He buys his own juice now, gets me to build his cois, has two of the exact same setups in case one breaks, vapes ONE juice and carrys an Ego One with him fully charged in case something goes amiss with his setup.