In my opinion, putting a good atty on a cheap mod/battery device is... eh. 1st & foremost I think you should buy a good mod. I highly suggest a regulated device. They're safest, you can control how hard or light of a vape you get off of any atty and they're reliable, show ohms, battery power, etc.
Especially since you don't have any experience wrapping coils and are after clouds, you're probably going to tempted to make sub ohm coils, which I would not recommend for a newbie unless with a regulated device &/or having done plenty of homework on batteries, etc like steved said above.
For $100 your options are pretty limited.
I would highly recommend a Provari, DNA20, or DNA30 device. You
might be able to find one for around $100 in the classifieds. That's probably your best bet with that budget. There are a lot of clones out there made in China for cheap but I have no idea how legit or safe their DNA chips actually are. Some claim to have DNA chips, but I don't know if they're legit & wouldn't be surprised if they clone out the chips which might compromise their reliability.
The best and one of the only DNA tube mods I know of are from mark bugs... but they're also some of the most expensive. Titanium is a LOT more expensive than their stainless steel '
apprentice' line. Futura was a cheaper DNA tube mod but they've gone out of business.
I think your best bet is to find a used provari in the classifieds. -they're reliable and last a long time. I have one I haven't touched in years but I put a battery in it the other day and it still works like a champ & I have friends who have used theirs for years and years without any issues.
There's a lot of cheap RDAs out there and you'd be surprised at the clouds I can kick from a 1.5ohm coil. Further down the road, after you've gotten more experience, with vaping, coil building, etc. sky's the limit. But for now I don't think you can go wrong with a provari you can get a
classic for $160 new.