What is the negative effect of an unsed and unstarted?

English as a Second Language English Vocabulary, Grammar and Idioms
1
  1. What negative effect does it have on a car that have been sitting without starting for a long period of time?
  2. What negative effect does it have on a car that have been left unused and unstarted for a long period of time?
  3. What is the negative effect of an unsed and unstarted?
  4. Can you make an estimation of the cost for repair and part replacement to get the car back up and running?
  5. Can you make an assessment on the cost for repair and part replacement to get the car back up and running?

Are th above sentences correct?

2
  1. What are the negative effects on a car that has not been started for a long period of time?
  2. What are the negative effects on a car that has been unused for a long period of time?
  3. What are the negative effects of an unused engine?
  4. Can you estimate the cost of repair and replacement parts to get the car back up and running?
  5. Can you assess the cost of repair and replacement parts to get the car back up and running?