It's difficult to put a price on a w203 these days they can be from 16-25 and it's not like the 25 is going to be the best condition one or the 16 the worst one has to inspect each car and I bet each car will need work if you want to make it perfect but the basics must be right
Look for full written service history the only oil changes story won't work here
ATF, suspension, fuel filter and various other fluids must be done on time including recalls if it's a m271 engine.
Your father is right it wil defianately need momey to spend on top but initial price may be lower then Corolla grande so it can work out the same
If you intend to use the car as a daily driver and have no past experience with Mercedes or even what to look for in a workshop before even taking it to the workshop then I would say save yourself the trouble and just get the corolla, your father maynot buy into the German car experience
However get the basics right be willing to learn and spend a good amount of money but only once to fix it right first time you'll end up with a brilliant car and ownership Experince which is miles ahead then any Japanese car let alone a Garden variety Corolla
If you infact do goto see a car you want to buy just ask for a few things to check from me or toner Mercedes enthusiasts especially our resident guru Xulfiqar he will guide you best
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