I own a TLC 4.2 diesel manual and using from last 1.5 year. After buying, once enough efforts have to be exerted to have it upto the mark; if its not in good condition at the time of buying.
in my case i passed through the phases of injectors buying, diesel pump servcie twice, suspension work, brake rear valve, whole brake servcie, valve clearance, inetrior cleansing, meter caliberation, power stearing pump, AC service etc etc etc.
it was hectic BUT now its going much better now. Parts available but are costly no doubt (brake rear valve of Rs 7K kabli one !!! just a valve. kabli clutch booster i bought for Rs 8K) and sometimes kabli parts have to be searched even upto quetta. Rawalpindi is costly for parts purchase regarding TLC 80 series.
this is my experince (at lahore) that may be of some help to you. Checking the health of the engine, other experts would be better able to guide.