Advice for shipping from Canada to US?

I've had customs issues with USPS shipments from both Canada, Europe and Australia. USPS lost rare Technics SP10 power supply, ended up having to search and purchase another power supply, then lo and behold they somehow discover the original power supply months later. Also have experienced shipments from Canada held in US customs for duty payment. USPS doesn't act as broker, UPS,  Fedex, DHL are brokerage agents.

Have the seller contract with a freight forwarder on the Canadian side and have your amp customs cleared in the US and shipped to your door.  The forwarder has contacts in the US, both for clearance and transportation.  Sometimes it will be the same party who does both.  Of course, you two will have to negotiate the price for all this.   It ain't the cheapest route, but it is the easiest one for you.  

Contrary to the advice to avoid the postal service, I have had good experience receiving packages from Canadian vendors shipped that way including one received just yesterday.  I buy stuff all the time from Canada, really it is not much different from buying from US vendors.  The unknown factor X right now might be a change in the political climate, which we have zero control over.

As a Canadian who has shipped to, and from, the USA many times I would recommend you use either the postal service or one of the reputable couriers like UPS etc. Also ask for shipping insurance, it makes the delivery require a signature so no leaving the package on the doorstep. Small cost IMO for what you get, note it wont help if damaged but only lost. But it will make the delivery service treat it differently then regular packages, Ie signatures, duties services, etc.

If using a Courier like UPS I recommend you ask the seller to take it to a UPS store to have packaged and shipped. 

I have some Canadian audio equipment, these particular manufacturers use UPS. I also make other smaller purchases from other Canadian entities, Fedex Express also good. By all means don't use USPS, Fedex Ground or Home services, these are run by contractors, many horror stories. DHL another quality shipper I have experience with for European and Asian shipments, not sure they ship Canada to US.

Well, I'm taking care of all the shipping to facilitate the transaction.  I'm ok with the responsibility.  Good to know about the product codes on customs forms.

Do you really want to tell the shipper how to ship it?  You start making decisions and if something goes wrong it is on you.

I tell the seller "take whatever time you need to package and ship it safely.  I'm in no hurry."

Customs process is a different story.  They will have to fill out customs forms with a harmonized product code on it.  What code they choose can affect what duties you pay.  I'd do some research and suggest the proper code.  If they choose one for defense electronics or something with special laws it can delay and cost you money.

Jerry