Yep, best left to a professional anyway, especially if you are installing glass. Just my opinion.
Don't be too worried about DYI. It isn't rocket science, and if you know which jobs you need to back away from it is better. Removing the nett curtain and replacing it with a Spotlight special venetian is easy. You will need a drill and drill bits. Measure where you need the hole, mark with pencil, Drill a hole in using a drill bit of an appropriate size for the screw and screw it up. Fairly simple.
Painting, go for a well known popular 'white based' paint. Wash the room down with sugar soap, then do your preparation (filling holes and sanding) and wipe down again to remove dust. Don't forget the ceiling. If you have a bathroom heater/ fan it should have clips. Generally you need to turn the lights off. Unscrew and remove the bulbs, then undo the clips (undoing the clips first can cause the bulbs to break and they are expensive). Paint the ceiling, then the walls, then any trims. Use a specailised cutting in brush, and a cutting in roller thing (basically a pad, with wheels on the side, and a grip hold that can shift depending on the angle you are painting). It helps with getting a straight line.
Ring someone to professionally resurface the tiles, during this time. Make sure painting is finished before they are due to come.
Get the shower screen fitted after the resurface is done.
Don't forget a towel rail.
Well, that is how I'd go about it. Just thinking out loud. But I'm still a novice.