You don't have to buy an expensive emergency auto kit for your trunk... You can find an old small suitcase or bag and buy items and store them little by little to create the ultimate repair kit on your own.. some items we suggest are:

This would depend on how you drive, your weather conditions in your area, as well as charging system and overall health of your Auto. By standards, most Auto Batteries will last strong for about 4 years... However It could be less or it could be more...  Belts should be checked when You are having your oil changed for signs, of stress or cracks and again, driving habits and weather conditions can effect overall

First and Foremost.... REPUTATION by word of mouth... Ask your friends, your family, your co-workers.. Check for State Repair Station regulation numbers.. Don't just trust the first Auto shop you come too, don't Just take your auto to the First number in the phone book... Do your research, talk to the repair shop owner/operator and get a feel for the place you plan on using.. Just because there are a lot of cars in the lot, does not mean its is a trust worthy shop

Each Situation is different. If the Accident is not blocking the Flow of traffic the general answer is yes... But if it is not advisable of feasible to remain at the scene without disruptions than you may have to use whomever is called to the scene first.