How much does it cost to hire a bagpiper?
The cost of hiring a bagpiper depends on many factors including the length of the performance, travel distance and time, any costs (tolls, gas, taxes), special tune requests, etc. Additional factors like the bagpiper's years of experience or the local market supply and demand might influence the quote. Each bagpiper will have their own method for determining the final cost, but knowing it's a combination of factors can help explain some differences in price range.
While the variation from locale to locale and piper to piper makes it nearly impossible to provide a range, it is safe to assume that many bagpipers are not in the business of playing for tips* nor will it cost in the high hundreds (unless it involves overnight stays, flights, etc.)
*one exception may be for charity and fundraising events
Additional cost factors:
Especially if it's your first time working with a piper - it's somewhat natural to associated the quoted cost directly to the time spent performing. Because it's easy to subconsciously form this association - a price quote can sometimes result in some sticker shock; but it's important to understand the full context in terms of preparation, travel time, and the actual performance.
Even if the musical performance itself only lasts 20 minutes, the bagpiper is still investing time "behind the scenes" including bagpipe maintenance, dressing in uniform, traveling to and from the venue, pre-event rehearsals, transposing, learning, and practicing any non-repertoire tunes, etc. (not to mention the financial investment to maintain the instrument and uniform!)
So what on the surface might appear as a 20 minute engagement could in reality add up to several hours in total.
To give an example, the cost of dining out at a fancy restaurant isn't limited to the short period of time spent actually eating, but rather takes into account the cost to the restaurant in purchasing the food, the skills of the chef and their many years of practice and refinement, the quality of service provided, etc.
Reframing the quoted cost in this context offers up a new perspective on the quoted rates of many top-rate, professional bagpipers.