Are you first owner of this car?
At 88 thousand km's the engine shouldn't reduce oil.
If you have planned to go for an engine swap with Cultus G10B EFI then go to scrap yard's and look for clean engine get the compression tested and make a deal with complete wiring, ECU, gearbox.....
The engine alone will cost you around 80-85 thousand rupees G10B is really expensive in market. Mechanic and electrician will take approximately 10-15 thousand rupees.. In short the swap can cost you over 1lac.