OIL pump is one of the main parts which mechanics neglect while doing engine job and it fails later making all the effort vain.
now u have the car, maintain it and keep it as "amanat" of company. you will surely get rewarded.
as for the kharacha is concerned, 6 month back my relative had the engine overhaul job from some cheapo mechanic in 25k just to save bucks. that engine lasted only for 6 months and then last week i had to get the engine job done of same car from jameel autoes, it costed 80k including labour, parts, head job, rings piston etc, new radiator, water cooling system restored to original specs. carb repair, alternator, still some engine parts were reused as they were ok.
coolant used, thermo valve and auto fan installed. The previous mechanic had changed the original carb without their knowledge and put some repaired.
this is what happens when ppl try to save money and get mugged by these road side goons.