As an ex-IT Manager/Systems Admin on mixed OS LAN and WAN locations I would offer this advice:
1. Did you ask why this person cannot do the work at work?
2. How does this person have the authority to have you do this?
3. Who will carry the can if this person downloads all the confidential files and goes away/ loses the laptop/ gets mugged by the competition. That person will be you!
So you must obtain documentation for this activity before you even begin to search for a solution, documentation, authority and a budget. Users will ask for the moon and you must ask for the authority to give the moon.
One day a board member walked into my office/server room and after some pleasantries became angry because that person was unaware I had been authorized to spend $4,000,000 on brand new servers, databases, backup systems, redundant powers supplies and redundant air conditioning. It was all around he and I.
After a few more unkind words from this board member I realized that this person had never ever read any proposal, not even the synopsis of a proposal. From that moment on my life in their employ became intolerable as this individual had investigation after appraisal and ridiculous tinker toy proposals that were offered as alternatives and even though I had documented it all I was pilloried.
Never, ever, ever, trust a user, and especially not a mobile user.