Todays high tech engines seem to have some major issues with oil leak, for example the Mercedes bluetec, they all seem to have a problem with the oil cooler seal in the middle of the engine, this repair is a major one consist of over 20 little misc parts.
Engine replacement is the worst case scenario, this is the last resort if all else fails. We can source out a good used engine with low mileage from local suppliers.
case study
2007 Honda Civic 1.8L block has crack and is leaking coolant and is non repairable. Requires new engine, got low mileage 20k engine total bill was around $1500.
Engine repair oil leak Audi