Driving on the left isn't as much a problem as not having the proper and legal driver's license. The latest loophole the insrnace companies are trying to pull is that if you have an accicent in a foreign country, they- in some cases - refuse to pay and they claim they are within their rights because you were driving in a country and you didn't have a proper license to drive in that country.
The solution is simple...thru AAA or CAA you can purchase an international drivers permit which is accepted by most countries in the world...the cost is about $30 and the permit is good for a year and has your picture on it.
Consider this another form of insurance..and by having this IDP the insurance company can't claim you were driving in - whatever country - without having a proper driving license for that country.