Anything made of rubber or plastic on the car is going to deteriorate with TIME even if the car isn't driven.
In fact, when you're talking about a 20 year old vehicle low miles is actually worse in many ways because if the car was sitting around unused for months or years at a time then it wasn't cycling fluids and lubricants through all the important places. That allows the rubber seals to dry out and crack. If you start driving it everyday those cracked seals eventually blow out and begin leaking, potentially very badly.
Whereas the same car with 150,000 miles on it probably got used regularly and the seals may still be good for another 50,000 miles over 5 years.
Let me put it this way, if I had $14k to spend on a vehicle I wouldn't be buying something 20 years old. I'd be looking for something much newer and with normal amount of mileage.
Now if the car was $5k and that was your budget, and you had to choose between that car with 25k miles or a 2005 with 150,000 miles, then maybe I'd be willing to go a little older to get lower miles. But at $14k this "deal" is a no-go in my opinion.
EDIT: I just did a quick search for Rav 4's in my area between $10k and $15k and I'm finding lots of them around 2010-2012 model year with around 100k miles. I'd much rather have one of those than a 2000 with 25k miles, for the reasons's I described above.