Having a complete maintenance history greatly increases your chance of success and happiness. Considering the age of these vehicles though, there will be issues eventually regardless of past maintenance. Frame rust is a show-stopper. Things like the plastic window regulator guides and AC solenoids/actuators can go out at any time and could cost a small fortune to repair at a dealer. Ditto for some of the engine control systems. Many of these things can be fixed in your driveway with normal tools, a multimeter, and persistence. Hopefully you are somewhat handy so you can avoid costly shop visits OR you know an independent shop who you trust completely. This site alone has hours worth of stuff you can peruse and study. I think preparation and advance knowledge is key to handling problems quickly as they pop up. Find yourself a nice one, and Good Luck!

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma