You haven't provided nearly enough information for us to give you any useful indication of the value of your specific Rover. However, I'll venture this: I'm also in California and have a rust-free '92 RRC. I figure mine's worth somewhere in the $2,000-3,000 range. My leather is still excellent and headliner has not yet sagged but some other interior bits have suffered some. My stereo no longer works and i removed the sub-woofer, amp, and CD-changer from the rear for more cargo room. Neither of my rear windows works but that's probably just the relays. My AC does not hold a charge, despite my having spent a terrible amount of money on it. My body has a few dings but is mostly straight. The paint is not so good.
Those are the main negative bits and would probably make a stock RRC of the year, with its 142K miles worth about $1,000. However, mine runs well on the original engine, tranny, and xfer box, has a 2" RTE lift, Bilstein dampers, RTE tie rods and rock sliders, SG front diff protector, Ramsey 8000# winch in Ramsey (NLA) hidden-mount, endcapless front bumper (from a 2-door RR) with brush bar and aux lights, front Tru-Trac diff and rear Quaife diff, Cobra CB radio, and custom roof rack and interior cargo mount. In short, mine's well set-up for fairly serious off-road use and mechanically sound but shows the effects of years of having been used as it was designed to be used. It would probably be worth more as parts than it is intact.