Probably they won't need to do anything you can't learn to do yourself. If you want to tackle it yourself, look up youtube videos for

* change bike tires/tubes
* adjust bike brakes (caliper, not cantilever or V-brake or disc)
* adjust rear derailleur
* adjust front derailleur
* clean and lube chain or replace chain
* replace cables and housing (reattaching new cables requires knowledge of adjusting brakes and derailleurs)

and that should probably be everything you need to get it on the road. Tools/supplies needed are screwdrivers, tire levers (or careful use of screwdrivers to get old tires off, hands only to get new tires on), metric allen wrenches, chain lube, chain tool (or dremel cutoff wheel?), and cable cutter (or dremel cutoff wheel)

Some advanced things that might additionally be needed for a bike that old could be
* open hubs, clean out, replace ball bearings with fresh lube
* remove cranks, open bottom bracket, replace bearings with fresh lube
* open headset, clean out, replace ball bearings with fresh lube
(are you seeing a theme here?) More specialty tools are needed here (freewheel/cassette removal tool, chain whip, cone wrenches, crank puller, bottom bracket wrench, headset wrench)

But if the wheels and cranks and steering seem to turn ok (smooth, quiet, no play side-to-side), you may well be OK for that advanced stuff.