People using space heaters, how high is your power bill?
It's pretty hard to compare your power bill with someone else's and know who's paying too much, unless you have two houses the same size, insulated to the same degree, in the same place, inhabited by the same number of people, with the same appliances, heated to the same temperature, but with different heating fuel. I have an electric forced air furnace. One winter, as an experiment, I didn't use the furnace except for at night for about two weeks when it got below freezing. It's a mobile home so the heat ducts help keep the pipes from freezing. My heating season runs from about the end of September to sometime in April. Instead of the electric furnace I used two oil-filled plug-in heaters. My electric bill that winter was almost the same as the winter before and the winter after, all 3 years within $50 of the same amount. Electric heaters, whether they are sitting in your basement and attached to a fan and ducts or plugged into an outlet, produce the same amount of heat from a given amount of electricity. Your heating cost would be about the same as using the heaters if you had an electric furnace. If you heated with wood, or gas, or oil, or coal, then the cost could be different from using electricity.
Last year, my son and wife both used them on a fairly regular bases, my son in the shed, wife in the common area where she set up a desk to work from home. Vastly different winters temp wise but I receive quarterly reports for energy use from my power company. How much we use compared to 100 of our similar neighbors BS. Went from above average to average this year.
My bill is $165/mo. with an average outside nighttime temp of 34 degrees right now.. Three 240v heaters, one 120v heaters. 1200 sq ft house with inside temp at 68 degrees. Power is cheap here, so yeah, yours seems about right.
A space heater running full power will use 1.5 kw/h per hour. At US average 13.5 cents per kw/h, that's $4.85 a day. Fortunately they normally cycle off when room reaches thermostat setting, but that could cost you almost $150 per heater per month.