Spend the money on the carfax. Better, have the seller do it.
Ask about transmission repair history especially but all repairs in general.
I don't think these have many more issues than any other vehicle I've owned but there are some big ticket items that can do some serious damage to the wallet. If some of these have already been taken care of, you're doing well. Mine is on it's third transmission, all replaced by the previous owner, and the third should be good for another 80k miles, more than I'll ever put on it.
Most repairs won't be on the carfax (the transmissions were on mine, for some reason) but I think a ford dealer might be able to run the vin and tell you what all has been done at a dealership level. And can check for recalls, too.
There's some Ford techs that are here that might be able to run an Oasis report (Ford report giving all specs, options, recall info, build date and dealer-performed repairs). If you have a dealer nearby and have the VIN, it's worth a shot to ask.
Good luck!