Replaced bad coil

80 year old mother limped her car into this shop. Doug evidently diagnosed the problem as a bad coil and did the repairs for $400. Trouble has been after the repairs - Doug Sr. has been a complete ass and prevented Doug from explaining to Mom the nature of the repairs and if he actually fixed the source of the failure - horrible after the fact service and communication. All Sr. wants to do is belligerently point out how long he has been in the business - totally irrelevant to our need to understand the repairs done on Mom's car. I'm not sure what they are hiding but I guess time will tell. Very difficult situation and as the consumer you would think Doug wouldn't mind explaining what he did and why.