Dear unfortunately our market is very bad in this regard, even in such a budget it is hard to find a car that is sedan and reliable to run.
Coming to your 3 options: liana eminent vurv is a good choice/1600cc one. Problems of this car are wiring/fuse issues in rain, and problems due cng use.
Platz: parts are problematic. Remember, its at least 12+ years old, so it will need some maintenance naturally. Unfortunately, finding right mechanic and spare is hassle. Resale of vehicle is non existent.
Lancer: Enjoys better reputation than above. Spares are plenty easily found in Lahore. There was a 1500 cc version, (if I remember correctly) which had wooden inside paneling it was imported. Try to get that.
Conclusion: In my humble opinion biggest maker of sale/resale or biggest destroyer of any brand in Pak is one : maintenance. With that in mind, if you want to go for sedan, I suggest Corolla (98-2002), its tough, robust, easy parts available, and most mechanics can work it. But stay away from diesel converted to petrol car, either go for original diesel or original petrol. 2nd opinion would be city (2000-2001) and finally 3rd option 96 onward civic.