Wanted to Buy a used 2008 E70 X5

[The Expendble]

Hi guys,

I wanted to buy a used 2008 model X5. Initially i was planning to buy a 2014 model costing $29,000. But then i decided not to buy because of following reasons

1. I have to pay $500 every month for 5 years. Its a pain to see this money deducting from your salary for 5 long years
2. 2014 models have similar mileage run comparing to older models
3. No warranty
4. I hate the exterior design of current gen x5. Both front and rear. E70 is pure beauty.
   

The previous gen's costing only $6000, and thats the trending price in my region and i need to pay only once and i can afford to pay. Mileage is close to 100k miles.

I have some concerns before i buy. Yesterday i went to see a car and test drove it, all good. I confirmed i will purchase and took to the car to registration centre with seller.

The inspection has to be done first before owner ship transfer. The inspection failed with following reasons

1. To Repair Engine. Excessive oil smoke from Exhaust
2. To do Wheel Allignment
3. Body Scratches

My Qns:

1. When i started the car why it didn't pop any error for any Engine oil leakage? As well as why no errors shown for disallignment of wheels?
2. Is it possible by seller to remove any errors by coding?
3. what is the cost of repairing the engine oil leak today for a 10 year old car?
4. Even if i repair, i am afraid it will occur in next few months?

I am skeptical now because in 2 to 3 months i may get surprises and i cannot afford to repair this car continuously. But i really love the car and is a steal for that price.

Need some inputs how to deal with these situations?