Losing water???

My 2001 Jimny seems to be losing water, I’ve changed the thermostat and radiator cap. There isn’t any gunk in the oil or under the rocker cover.
The only thing I’ve noticed is it seems to steam up inside really quickly.
At the moment I’m filling the expansion tank every other day.
What else should I be looking for?
Thanks in advance for any help

Check for dampness under the center of the dash on the floor, if your steaming up inside my guess is the heater matrix or associated pipework.

I had the same problem last winter with my 2008 Jim and, like you, asked for advice on this excellent forum because I was thinking of the easy & cheap option by using a sealer. At the time I suspected the matrix. As the car was undriveable with the windscreen misting up, I clamped the heater hoses to keep me going while I did some research. I was strongly advised by forum members not to use a sealer as it would wreck the engine. None of my research indicated anything so drastic. A few months ago I added K-Seal to the coolant and the leak is now 100% cured. I still get a slight coolant smell in the cab but that will be the carpet still drying out. It is still a bit damp but slowly being sorted with newspaper. Despite what I was told, I would strongly advise giving a decent quality radiator sealer a go.

With steam inside the vehicle (this should also be accompanied by a sweet smell); this sounds like either the heater core or the hoses going to the heater core are leaking. If you do not need the use of the heater; you can disconnect the hoses going thru the firewall and bypass the heater core. This will be a quick fix until you can get the heater core replaced.