Hey guys i need a little help.

First, last week car won't unlock, so i manually unlock it and go to start it, car starts then immediately dies. It does this 3 times before locking me out.. disconnect the battery... reconnect.. same thing happens. get the car towed to a mechanic my family has used for years.
They call me later saying that i need a new starter and a new pulse module. After he tells me this i specifically ask him if he checked the SKREEM and the RCM as that what i came across in my research and he says yes and both are fine also he tested the starter out of the system and couldn't get it to engage. I say okay cool.

Fast forward a week later and after he installed everything now says that the SKREEM MODULE needs to be replaced. Wasn't the same guy so i held in my anger and just said okay bye. So now i come to you my saviors with a question. Could my starter have actually been bad? because i feel they are going to try to charge me for both. I'm not the greatest when it comes to cars or know the function of most parts but i was thinking that if the car DID start (then immediately die) that the starter should be fine am i correct in thinking this? just wanted to argue when i go to pick it up and they try charging me for all of the parts.

As always thanks for any help i greatly appreciate any help i can get.