I want to buy new speakers for 50,000 and see it used for 30,000, what should I do?

Offer 25k for half price on the used pair. Never once had a problem buying used speakers. I only buy from sellers with a perfect rating and a good amount of sold items. Also depending on your payment method you should be covered should the item not be as described. 

To save $20k, buy a $500 airline ticket and go see/hear them.

If you want to pay 30k for used then look for used speakers online. 
Email some retailers for demo models 

should be pretty easy to find $30,000 speakers used 

For that kind of money, and potential savings, spend the money to visit the seller and get a demo. 

Who doesn't love instant depreciation? Buy new!

Spend the $30,000 used then use the $20,000 to feed A LOT of malnourished kids...

My personal experience is this: I have purchased speakers used that I could not afford new. In my case I was happy with the used ones and the 11K I saved- which went into a good DAC. I was happy with the allocation, Additionally the mfg. warranty transferred. No issues arose and I use them to this day. 

I have also purchased new. (times change, wealth changes, etc.) and I was not especially bothered or impressed by "brand new" although the speakers were and still are impressive. 

It's totally an individual thing. To me my AMG 63 was a steal 18 mos. old. I saved 35K. It felt new to me. So did the used speakers. Because I'm a number nerd I consider how much 25K or 35K is worth in a decent investment multiplied by 20 or 30 years, As Warren Buffett says "It soon appears indefensible".  I'm 62. That wealth will get used either by me or my heirs. That's defensible. Meanwhile I have luxury for "relatively cheap". 

If you’re spending that much, go inspect in person, listen, heck even tote your amp and cables. You can afford the flight, a first class hotel, steak dinner with a bottle of Lafite to celebrate purchase with what you’re saving! Unless you hate them, then you’re saving more.

I would buy the used speakers if and only if I could see/hear/touch them beforehand.

I've never considered the fact that I have a wife unfortunate or unlucky. Guess it all comes down to choices, eh?

I don’t believe you are crazy. 
 

I have a good relationship with a local stereo shop - and I go there for all my purchases (new or used). They deliver, set-up and stand by the product. On demos I get the warranty and in some cases manufacturers (e.g., Wilson Audio) have certified used programs. 
 

Good luck!

@OP - your post does not raise a concern that very nice speakers are too expensive. With very rare exceptions, consumer goods depreciate. Not nice speakers depreciate and very nice speakers depreciate. Actually, very nice speakers depreciate less.  Speakers have a long service life so their depreciation can be amortised over many years. Anyway, that has to be set against the pleasure of listening them, and what price does one put on that.

$50k buys you a lot of speaker new or used. Call Mike Powell @11stereo.com. His F&F lineup is very good and he always has high end used gear for sale. I have made several purchases from him and he is good people.

I would suspect 50K speakers haven't had a very hard life. There are very few 50K party speakers.  The other option is to find a used pair of even better speakers for 50K.  You would be less likely to want to exchange them in the future.

I have owned many speakers that msrp’d in the higher end brackets, never lost anything when I rotated them out. I buy such items used, etc or negotiate some cut even price with some dealer/others (helps if you know people). If you are not sure you will hang onto something for life/a long time, try and buy at a ’cut even’ price.

Would you be buying the used speakers from a dealer? If yes, do they offer any kind of guarantee or have a return policy?

If they are newer speakers, replacement drivers are probably available, but I'd check.  I'd be concerned about buying an old set of speakers.  Drivers go bad with age and replacements might not be available.

I've never bought used speakers, but for $20k, I would consider it if they check out. They may have been owned by someone like me. The used stuff that I've sold was in like new condition. 

Can you see and listen to them before purchasing? If not, do you trust what the seller tells you about the condition and how well they were taken care of and how hard they were run? If not, then buy new and don’t look back. @tony1954 makes a good point, there are tons of incredible speakers much less than $50k. And to @dwcda point, do you have the associated gear to get the best out of a purchase like that or will you be upgrading the rest of your gear? Buy what you want/like just make sure you’ve thought through where you’re trying to get to.

I’d go new. They will immediately depreciate like a car would but should satisfy you for years, decades. Will you be upgrading the rest of your equipment next? You looking at Sonus Faber Amati or Stradivari?

helpful.

Don't stop at 50k . . . go for 100k.

I would get a divorce .............soon

They are out of my budget, but I am guessing that one can find excellent speakers under your $50,000 budget. If you worry about depreciation or buying used, then perhaps you should adjust your budget to a value that you are 100% comfortable with.

@emergingsoul curious can you share which 50k speakers you are considering?

PS I bought my nice speakers as demo's, from a dealer who (like GDP says), installed them and stands by them.  This may be the best of both worlds.  Cigarette smoke smell would be a killer for me.

Buy what you want; you are not insane.  New or used is a personal preference.  Do you buy a new car or will you buy a 2 year old one with 20,000 miles for this similar discount?  Most nice equipment is actually cared for extremely well.  Look at the entire system, call the seller.   you can tell.  Probably.  :)

This is definitely a personal thing. It depends on your personality.

If it were me, I would be planning on keeping these speakers for ten years or more. I would be incredibly disappointed in spending $30K and getting something scratched or banged up, let alone if there was a sonic problem… I would probably slowly realize. For me $50K is a lot of money. Also, my dealer would give me credit for them if I chose to upgrade in five years. He will come and set them up. But that is me. I want absolutely no uncertainty involved in a large purchase like that. If I bought used and they were all scuffed up… I’d end up selling them and buying new ones. That is me.

Some guys would be proclaiming what a genius they were for getting such a bargain and they would love that every time they sat down and listen to them.