How to buy Q990D under $750

Use Samsung EPP discount, that will bring down to $900.

Then talk to Samsung chat support and ask for 10% discount. (Say you had Samsung devices before).

During the purchase use Rakuten extension and activate it. (I recommend extension to help with tracking a bit more). Rakuten has 10% cashback for Samsung soundbars right now.

On top of that, if you have AMEX BCE card, that gives 3% back for online retailers. Or even Paypal, check their cashback reward offer, they sometimes have 2.5% cash back.

After you make the purchase and receive the product, you can try to request for return/refund, oftentimes they give you back like $30-$50 back just for you to keep it. (Not the most ethical way).

Even with taxes, all of it will probably be less than $750.