Is it possible to lower cost of living?

Yes, if you have economic growth, with little inflation, or if u have free healthcare, or no trade barriers etc etc

Yes. The trick is to have money keep its value. Put another way, don't devalue the currency. If the currency is devalued the price of things go up.

So how to do this? There are 2 ways. There is the gold standard. Money backed by gold keeps its value. The other way is to have the Feds target the money and produce the right amount of money that the economy needs. Not to much and not to little.

Having money keep its value is just one leg of the problem. The second thing is you need to grow the economy. Ideally you want an export economy. Exports brings in money into the economy. Which makes the currency stronger.

A strong dollar will increase the purchasing power of the currency. If your money is strong you can afford to buy more stuff. The result is a lower cost of living.

Yes.

Yes, remove non-essentials!

Technological advances will do the trick too!