Dr says Change Warfarin to Xarelto to prevent strokes.

Check the price of Xeralto or any of the alternatives and your insurance. That may stop you right there.
I am on Warafin and also reduced sodium(2000 mg per day). I have no problems with what I eat. You do need to get informed about foods containing Vitamin k which counteracts the Warafin.
You can get down to 4-6 wks between testing.

In my younger years we had an egg farm and used Warafin for rat killer. It thins their blood and they bleed to death. Of course you are not taking it at that high a dosage.