Total Valuation Loss Discrepancy

Are insured entitled under any law to obtain 3 estimates on a car's value if they don't trust the insurance company's paid adjuster (who renews his contract with the company only by saving them money, not by costing them money). A friend's brother-in-law ran my car's value on NADA and came up with a value of roughly $5700 and my insurance company's adjuster is saying it is worth $4100. It's a 1999 toyota camry le 4dr sedan; 4 cyl., 2.2 liter. It's options are: automatic transmission, air conditioning, power driver's seat, heated back glass with antenna, electric remote control mirrors, cruise control, power windows and doors. No moon or sun roof. It has $159,600 miles on it but was in excellent condition prior to the accident-- even brand new tires and wiper blades; but the adjuster won't list it as anything better than andquot;goodandquot; condition in obtaining his figures. (Of course, after being totaled it isn't in andquot;goodandquot; condition either, but that's as good as the adjuster will go.) Is there a way to contest the company's adjuster's value? Do I have a right to get other estimates on the car's value? Is the $5700 NADA value my friend's brother in law gave me in the correct ballpark instead of this $4100 stuff the insurance company is trying to tell me? Further, because I like the car and want to keep it and fix it they want to knock an additional $1200 off of their settlement check. (Initially they said it would be $800 to $1000 and my wife and I wanted to discuss the offer first. When we talked to the company the next time they said they had made a mistake and that they were taking $1400 off because we were keeping the car. We said that if the car was suddenly worth that much more that they were losing an extra $400 to $600 by letting us keep it that the car's actual value must be more than the $4100 they were trying to tell us and that they therefore ought to be reevaluating the car's value (up) before taking the $1400 off. They went only far enough to say that they would be doing us a HUGE favor, but were willing to adjust their withheld total down from $1400 to $1200. The whole negotiation with them has been nothing but swinging at a moving target and I can't help the feeling that we're getting a royal screw job. The company is urgently trying to settle the claim and pressure us into taking the deal and my wife wants to because she is just tired of fighting it (I'm sure the insurance company depends on that), but I always want to fight harder when I think I'm getting a financial screw job. Any guidance from the experts that might help??? thanks!