I agree, that price seems high to me. I just configured that set up (only with a 10' rack) with L/S and microhandles and brand new it came out to a $16,319.00. I didn't include any of the extra feet, those usually run around $40 or $50 depending on the foot type. If you can get her to knock a couple thousand off that would be an awesome deal.
I love my Innova. I got mine in 2010 and it was a dealer demo so probably a year old at purchase. I wheeled and dealed free delivery and installation. I also had them throw in an open toe foot. Mine has the old style closed foot so is high enough to use as a ruler foot with no issues. The newer models the closed toe foot is not as high and while you can use it as a ruler foot you are better off buying one for the newer machines. I have since upgraded my standard SR to L/S - totally worth it!! When they installed he gave me a quick hands on lesson in loading, threading, changing needles, flipping the head, adjusting tension. Probably about an hour and a half walk through. I had previously taken a class at another dealer as well with an HQ machine(so I could rent, but that never happened). The idea of 5 free lessons from the dealer is very appealing. Most hands on L/A classes at the major shows run around $300 for a 4 hour class. I don't have micro handles and I have done micro work without them. My friend made her own. They don't have off on buttons on them but are perfectly functional. You may not need the micro handles. Even without the warrantee Innova offers free 24/7/365 phone support. The machines are so well made you probably wouldn't take advantage of any warrantee. Only you can decide if the warrantee, delivery and installation is worth the extra you would pay. For me, installation was a big deal. I wanted to play right away and I know from years of camping with my husband that setting up that rack on our own would have lead to a big fight between us. But my DH has done some mechanical repairs on mine when we had to replace a belt.
I would be hard pressed to decide which deal to go with (private sale or dealer sale). If you think you can disassemble the rack and reset it up with minimal heartache and you can get the seller down another 1 to 2 grand go for the private sale. If not, go with the dealer and don't be afraid to ask them to throw in some stuff like extra feet, bobbins, etc. or you can even be as bold as I was and ask for free delivery and setup. The worst that can happen is they say no. I have never seen them offer any specials at the shows.
Good luck with whatever you decide. IMHO you can't go wrong with an Innova, but I am biased.