This is probably the best place to start. A professional glass polisher is not cheap to employ. With charges starting from £350, your first consideration should be the value or replacement cost of the scratched glass unit in question.
For a single scratch or single window unit, replacement may well be the cheaper option. To give you an idea, a standard household, double glazed kitchen window (we only say kitchen window to give you a mental picture) can be replaced for around £65 by your local glazier.
Tip: For small repairs you may find a DIY Scratched Glass Repair Kit is a more suitable option for you. Read our notes on DIY kits.
However, if your glass is bespoke or made specifically to fit your design, or you have multiple units to repair, then a professional glass polisher can save you a lot of money.
If your glass window has a wooden frame, although the glass itself may not be expensive, the removal of the glass, fitting the new glass and redecoration of the wooden frame can often be very expensive, so repair is a viable option. The same applies to large windows seated into oak frames.
If your primary consideration is time rather than expense, employing a glass polisher is a viable option. Glass has to be produced and cut to size and then your replacement double glazed unit needs to be constructed, sealed and Argon filled. This can sometmes be time consuming. A glass polisher can be onsite repairing your scratched glass within one or two days.
Although glass polishing provides scratched glass repair solutions for almost any situation, employing a glass polisher will cost you money. You need to ask yourself (and we do not mean any offence when we say this) if you can live with the scratches. Very often, you will find them annoying because you know they are there. As glass is designed to be looked through, not looked at, other people may never notice the scratches.