Whether it makes any real sense or not, the current market does value 280 SLs from 1970 and '71 higher than other 280 SLs... and as Michael pointed out, so does the collector car insurance industry.
I think a lot of it has to do with newer Pagoda SL enthusiasts, like the original poster, who begin to research the cars and see this general thought that 'investment potential' is greatest with the later models. It's a bit of a chicken and egg thing. Did everyone start saying the later cars are worth more and prices started going up (especially the high end auction houses in the past few years)... or were people asking higher prices and then everyone figured they MUST be 'worth more'.
In general terms, sale prices ARE, indeed, higher for 70 - 71 models, all else being equal, than the 68-69 models.
Frankly, I think a lot of it is just hype. Don't we see the same thing with 1989 560 SLs? Are they any better than 1988s? I don't think so, but '89s are what people decide they 'should buy for maximum investment potential'... which might be the underlying issue. Buying and having a really good car that you love and enjoy has been overshadowed since the prices of Pagoda SLs essentially doubled in the past 7 - 10 years (along with a lot of other collector cars).
Folks just getting into collector cars, people who have decided they've been working all their lives and it's about time to reward themselves and put some money in assets they can enjoy (investments) really have affected the market over the past decade. I can think of one gentleman that I know.. between 2015 and 2016 he bought a 356 cabriolet, an Alfa Giulietta spyder and a 280SL... when he was looking for the 280 he called me and said 'I only want a '70 or '71'. I asked why... and he replied, 'those are the ones to have, right?'
I think it's folks like that, new to the market, casual enthusiasts, prepared to pay money right now, for cars they've always wanted who have had a serious impact on the market and driven things upwards so quickly.
I agree with the 'buy the best car you can afford' advice... but I'd add... 'The best car you can afford and that you really love'. Don't buy a green '71 because you think it will be worth more if you've always wanted a silver car with red interior and there's a nice '68 available in that color combo. Buy what you love, what turns you on, what you'll enjoy turning around to look back at as you walk into the coffee shop on a Saturday morning... if you want to talk VALUE for the dollars... consider a 230 or 250... I don't think you'll be disappointed with the power of either car.
If you want something really unique, buy as original a car you can find, with a good story you'll enjoy retelling, even if the paint is blistered and the interior is a little beat up. Anyone (with a bunch of money) can buy a perfectly restored car, not everyone can find and buy an original car.
