EDIT- My heating/ac is all electric so i cant do anything about that or gas and i cannot install a heat pump most likely because i rent and probably cant change large aspects like that

I’d like to have two space heaters (one i already have as a floater between bedroom and living room, its a small apartment)

Is it possibly more efficient and cost-saving to keep a minimum temperature to keep the “pipes” from freezing in winter but be able to surgically modulate the temperature using seperate slace heaters like if i stay in either room all day just use that room’s sh to get it comfortable but let the other room just chill at the min temp