we have a small pelonis ceramic heater. Its like 6" on all sides. Yes it has a fan in it.
as for the fan noise, studies have found you actually sleep better with a background noise.
I used to be a "road warrior" where I traveled 4 night per week. I can vouch for this. With no background noise I would lay in bed listening to everything and I would end up hardly sleeping at all. Turn on the room Fan and I would fall right to sleep.
even in the truck camper I prefer to have the fantastic vent turned on low at night (I have the full automatic fan with variable speeds, not the 3 speed that came in camper.