Onsite access to internal resource for multiple users - TS?

We will be hosting about 12-15 visitors onsite for some due diligence.  I need to give these users access to an internal web application that will host the data they need to view.  I need to lock them down to this one particular application, also blocking access to USB ports, printing, etc....Which means I can't have them just bring in their own laptops and plug them into our network.  So my options are to either buy 12-15 computers and create a locked-down image that they use to access the resource, or...I was thinking, it might be better to build an internal Terminal Server that they could use ANY computer to access, and lock down the server (no default gateway, no printers, etc...), which would also ensure that everyone was using the same browser, MS Office version, etc....  Would this be a good use of Terminal Server, and if so, what am I looking at in terms of purchasing/licenses on the software side?