I know of no "professional" propane distributor that would set a vertical residential tank. Vertical tanks are for dispensing to the public. Where I lived in the mountains I had a red 10# regulator at the tank, then a 11" water column 1,000,000 BTU gray regulator under the house where it was slightly warmer.
My 4'10" tall fifty, froze up at -22F. I then set a 500 gallon tank and had no more problems. Mammoth Mountain ski resort had 12 500 gallon tanks plus built in infrared heaters. I had to set four 500-gallon tanks for a a circulating floor heating automobile repair shop. The boiler was 1,125,000 BTU.
There's nothing quite like a freeze-up at -20F