1) I am looking at a new AR192. I figured that between me, my son, g/f, and parents that's plenty.
Hmm. When we started looking, I was going by the oft quoted axiom "buy your second boat first" and was looking to the bigger boats while my wife was leaning towards the smallest. That ended when we saw three of them side by side (at the OC boat show). IMO, hard to spread out 5 on the 19' - and remember that you WILL have friends that want to go too, starting from your son's, so your 5 is now 6 or 7. Like others have said, you really should look at the 21's and the 24's. (As I'm sure you know, a big part of the difference in usable space between the 21 and 24 is the head, or storage, compartment, not just 3' extra seating space as one might expect by the length difference.) I'm guessing you've seen the overhead shots and feature comparisons in this thread? https://jetboaters.net/threads/differences-between-the-newer-4-cycle-yamaha-jet-boats.29/
2) If I do look used, what would you suggest. My son and I love the water, so tubing and eventually wakeboarding would be ideal.
We went with an SX240 because of all the low bridges where we boat. A tower to raise/lower would be a PITA (2015s are much easier than the previous ones but still...). That said, if it weren't for the stupid bridges I would have bought a boat with a tower in a heartbeat. If you're considering wakeboarding, I think you'll find lots of confirmation here that a tower is the way to go. That's true new or used. (How old is your son BTW?)
3) The reason I am looking at new, is the warranty, to me that's HUGE, granted I will take a huge hit when I buy new, but that's something I need suggestions/opinions on
As you know, we were able to find a 2012 with three years of YES on it so I would not necessarily make that your sole criteria for the new/used decision... New boats come with one year - unless there is some sort of boat show special (which happens often it seems - see 4 - but will NOT happen now until the fall. There are plenty of (used or new old stock) boats available with warranty. CALL YES with the hull number [866-YES-EXTD (866-937-3983)] and confirm that everything is good to go as far as they are concerned. There was a problem with the registration on the boat we picked - and in the end it worked out very much in our favor.
4) Will Yammy dealerships deal at all ? I haven't ever bought a boat new, but I have haggled with salesmen over cars ?
Ummm, not exactly! There's lots of info on here (example: https://jetboaters.net/threads/what-kinda-deals-are-people-getting-on-15s.4424/) but basically there's little or no movement (again, seems to depend on time of year) on the base price BUT they discount or throw in "extras". (Different from a lot of the other boat manufacturers where you see "show specials" like "MSRP $90,000, show price $60,000"
5) I am torn on this one, Do I look for a marina that has a lift, and pay the 3k they want *OUCH* or do I just carry it to and fro ?
There are tons of public ramps around my area, so that's a benefit.
Where are you thinking of boating again? How far is it from home to water?
We're still waiting for the permit for our lift (sigh...) and the novelty of going to the ramp is wearing off quickly. (Last time I got into an argument with four teenagers that insisted on crabbing and standing on the damned boat ramp!! And, according to them, all I had to do to not run them over is to "learn how to back up the f'n trailer". (For the record, I have threaded trailers into spaces mere inches wider than the trailer - so it wasn't the trailer that was worrying me!)
The tradeoff to having the boat on a lift instead of your driveway at home is that it won't be around for you to modify during the season!
6) When storing in the winter, I planned on just getting it wrapped, covered and leaving it at my buddies house.
How big of a no no is this ? Do you suggest a climate controlled area ? My place I live at now I don't have a garage, so that's an issue
That was my thought too - snow load not a big factor around here, boats are easy to winterize...
But then I found out that shrink wrapping is about $12/ft or about $275 to $300. And OCMD pointed me in the direction of a place nearby where we boat that does inside storage for $90 a month. for 5 months, that's $450 - and to me the extra $150 is worth it. (NB: I've heard prices from $70 to $120...)
7) What are any suggestions you may have to a "beginner" at a jetboat, but have been in the jetski business for over 10+ years.
"Beginner" too so I'll defer to the "pros" on here. That said, it's a BIG and MUCH more powerful jetski! 
All I can say is that I have NOT found it as difficult as some.
8) What are MUST HAVE mods
thats always a good one, I know you guys will burn $ in my pocket LOL
Step one, IMHO, is to replace the factory trailer roller - whether you buy new or used, and even if you only use the trailer to tow it from where you buy it to the marina - with a Stolz roller. That POC will make a mess of the bow of your boat in no time. Plug locks. And then a keel guard if you ever consider beaching the boat (I would think it would also protect the keel if you use a floating lift. Of course there is the fin/no fin debate. (Beyond that - this site can cost you hundreds, if not thousands is essential mods!
9) What exactly does the YES cover ?
http://www.yamaha-motor-yes.com/docs/Yamaha_YES_Highlights_color.pdf
Note: the most common failure point seems to be the audio system - and it's not covered! (In any case, most people here will tell you that the best thing to attach to the stock radio head unit is an anchor rode...)
10) Any tips/tricks you can suggest
Other than reading all sorts of stuff on jetboaters.net? 
Looking to keep it at around ~35k
Ah THAT is easy! That's about $5k above our target for used and we ended up with a pristine, warranted, inspected, low time 2012 SX240 (after a lot of hunting). A quick look on BoatTrader tells me that for that budget you can get a new 2015 AR192, a 2014 AR210 (both zero time), or a 2012 AR240 (such as http://tinyurl.com/npc59z2 for example) but that option may involve some driving! (2011, OTOH, easier to do but harder to find with warranty).
This after she didn't want any boat to begin with. 
