How to heat

Semi-related question: within the shop I’ll have a lift, air compressor, welder (all 3 will require 240v), and several 120v outlets throughout. Will 100A service be enough?
Absolutely! That's what I have in my 33x30 shop WITH a 10KVA electric furnace. It is well insulated. I leave the shop at 45-48 degrees in the winter when not in use and my electric bill raised about $60 a month.