Maximum PC

Hope this is the right place...

I have a friend that has no home internet, only myfi. She wants to connect her myfi to a router and then connect her desktop, printer and laptop (wirelessly) to it.

Off the top of my head, I told her she would probably need a bridge or repeater. She currently has a WRT54GS router which I am pretty sure isnt up to the task. I have an dgl-4300 that I can give her but am wonder if there is a way to make this work with what we have.

If not, what is the cheapest solution for her?

Thanks for any help that can be provided!