It's still up to you sir, tampered or not the odo, if you're not or can't be sure, just check all the things mechanical, also check the casa record, usually cars that are still under warranty are subjected for casa maintenance 2-3 years. My girlfriend's honda city 05 1.3 cvt just finished her 40k km check up and still runs pretty good (she drives through long trips), she just replaced her busted headlight, that's all. Yeah, it's expensive compared to other parts but you're paying quality products bro, just a piece of advice. Original mitsubishi parts will really hurt your pocket but expect excellent quality (it lasts better than other brands IMO).

Again, ask for lowering the additional payment. say, 120k or less, than all's good if you want that city.