This is a a common problem. She can have the interlock device installed on any car she regularly drives including a family member's car or friend's car. She could also have someone go with her to test drive the car before purchasing.
The DWI Statute does not seem to require the actual installation of the interlock. It requires that it be installed in the vehicle principally used by the person suspended for DWI. Her reinstated license will have this condition and if she is found driving she will be subject to the punishment in the DWI statute. By the way, the suspension had to be for 3 months or at least 7 months not six. If she does not own a car I do not think she has to install an interlock. But there must be an interlock on the vehicle she drives. So she could install it on another car. In short, I do not think you have to show a receipt for an interlock but she would be unable to drive for 7 months plus the interlock period. She would have to install it on a car owned by her or principally driven by her. I am not totally sure I am right but that is what the Statute says. One of my colleagues will correct me if I am wrong. How she can get a car without ID is another question but solvable in a number of ways.
She needs to install the IID on any car she drives and present proof of same to the MVC to reinstate her driving privilege. There is no way around this requirement.
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