Recently over the holidays me and my girlfriend were driving to visit family (approximately 280 miles). Once on the way up and twice on the return the engine seemed to drop the clutch. This happened only when I (or she) was stepping on the gas hard. I felt like 15 year old driving a stick! This is an automatic with only 70k miles on it. I know the old owner and can't believe he rode it hard. Is this most likely a sign that we will be replacing the transmission? Is it worth it on a car that was sold for so cheap? Is repairing it myself a bad idea as I am not a mechanic?

Any ideas would be great

ATXs are the weak link on all FWD vehicles. They need to be properly maintained, which usually means changing the fluid (and filter, if applicable) every 30,000 miles or 2 years, whichever comes first. If this has not been done, then it's common for the clutch packs, particularly for first and second gear, to prematurely wear and start to slip. With proper maintenance, ATXs can go the life of the vehicle. To me, it sounds like the transmission will soon need to be rebuilt or replaced. Before doing anything else, however, I would change the transmission fluid (and filter, if applicable) using Mobil 1 Multi-Vehicle Synthetic ATF. If this does not solve the problem, then it likely needs professional attention.