Originally Answered: Thinking of buying a 1972 Porsche 911 T 5 speed 2.4 coupe. Good Daddy, bad Daddy?
The last of the "long hood" 911s are among the more desirable cars from a collector and enthusiast point of view. Though the 911T was the entry level car, thus also the most numerous and least desirable of these (but still a great car, and not a bad bet to get as far as it is likely to gain in value).
$7800 sounds like a low price for a good condition car. I've noticed all of the early 911s getting more pricey in the last few years, and this is about half of what I would expect of a car somewhere between good and excellent condition. As such, it is worth taking a closer look at the possible problem spots. First, it is unlikely to find a pre-galvanized 911 without ANY rust unless it's been restored. Even the California cars of this age will often show some rust - it would be worth your time on this alone to have a knowledgeable Porsche mechanic do a pre-purchase inspection.
As for the oil leak, again worth the opinion of a good mechanic, but the truth is that the older air cooled cars often leak some, and that if it is only some it's probably just a result of age. And the transmission sounds normal - the 901 5 speed which is in this car requires a little patience and finesse.
It's a fun car, and if you find the quirky aspects of these cars to be "character," then you've already been charmed (personally, I find these cars extremely charming). But it is worth taking a step back and looking at the car... at $7800, the car could be a fantastic buy. Given the increasing rarity of these cars, you should see prices go up (again, my experience has seen 2.4L 911T models going in the mid teen to $20k range). But that is IF it is really in good condition, and is either as original as possible (or has good documentation on any major work... since something like painting can be done to hide rust problems).
Porsches are well built and reliable cars, though like any older car, something of this age can be susceptible to various issues. And major problems can be very expensive. Make sure you do all your homework, and find a good mechanic to take a look at it before buying (a cheap Porsche can too often become the most expensive car you'll own). But as I said, if it is really in good condition and not suffering from hidden problems, it sounds like a great buy (and while the rear seats would be punishing for an adult, they work quite well for children who, in my experience, often enjoy having seats that are sized right for them).