Here's some info:
Buying a 1st Viper Tips
1. Establish your financial range.
2. Determine what is affordable in that financial range.
3. Do the above by searching ebay, autotrader.com, cars.com, and especially the viper club sites, like viperclub.org, .com, and viperalley.
4. Contact your insurance company to get your insurance rates to confirm that the purchase will be affordable.
5. Determine any other limitations you might have, such as mileage, mods, and color.
6. When you find a car you are interested in, you will need to check the car out, and to do this, do the following:
a. first with a carfax report, a check of dealership records on the car, and whatever information the seller can provide you (including on maintenance).
b. then get the examined, either by yourself if it is near (and be sure to familiarize yourself with what needs to be looked at), or if it is at a distance, politely post (on all the viper forums) a general request for a viper owner in the area to check the car out for you.
7. Bargain on the price, and make sure ALL arrangements are clear before traveling to get the car, and if not previously personally inspected, make sure it is clear that the deal is contingent upon your final inspection.
8. Buy the car and make sure you call your insurance company before you go anywhere and get it covered!
Other Notes:
 Have it checked by a Viper Tech if possible
 Get an extended warranty if possible (find out in advance)
Buying a used Viper
While doing my research on used vipers, I assembled a general list of questions that I wanted to get answered, some of which were dealer-specific (at the bottom). It does not have year-specific questions. It does have a few RT/10 specific questions though. Hopefully this can be of help to you.
Used Viper Questions:
General:
1. Year?
2. Price?
3. Mileage?
4. Clean title?
5. VIN #?
6. Existing lien?
7. In service date?
Equipment:
1. Stock /original, minor modifications (K&N filters, smooth tubes), or more?
2. Exterior and Interior Color? (stripes?)
3. Nature of CD player (single in-dash, trunk player, etc.)?
4. Soft-top, hardtop, tonneau?
5. Bag for soft-top?
6. Bikini top and bag
7. Car cover?
8. Existing warranty (or provide additional)?
Condition:
1. General Condition (any nicks, scratches, window cracks, etc.?)?
2. Involved in an accident, damaged, repainted, etc.?
3. Condition under front bumper / spoiler?
4. Condition of top(s)? (Soft-top sagging? Exterior condition?)
5. How maintained? (One owner? How long have you had it?)
6. Leather condition? (Split/cracked?)
7. Tire condition? (Reasonable tread?)
8. Floor mats condition?
9. Smoker / non-smoker?
10. Nitrous used?
11. Used for track events?
12. Condition of the rocker panels (underneath)
13. Condition of inside door rocker area
14. Scrapes under front bumper / spoiler?
15. Bottomed out?
From a dealer
1. Processing fees?
2. Taxes? (out of state?)
Differences between Gen I and Gen II: there are three big ones (besides the exhaust) that stand out:
1. The engine
The majority of reference to "Gen I and Gen II" refer to engine changes as there are several differences between the two engines, not the least of which is horsepower: The latter Gen I was rated at 415 (I refer to Gen1.5) and the Gen II is rated at 450 (ACR & GT2 rated at 460 due to smooth tubes and filters).
2. Suspension
96 RT/10 had the upgraded GTS suspension pieces
3. The hood
On the Gen I they have "smoothie" hoods with no NACA duct between the headlights and no vents above the wheel wells. The cars look different from the front with these changes.
That said, I can tell you that both are a blast to drive. You can't go wrong with any Viper. Period.
In addition to many mechanical changes, there are lots of changes from Gen 1 to Gen 2 Rt/10 you can easily spot. Windows, airbags, steering wheel, differential housing, even how you open the door, the spedo was increased to 200 mph...