Decks, Patios, Porches and Docks - Adding heat to 3 season room

I've been changing my 3 season room into a four season and am looking to add a heating system. I have looked at putting in a gas fireplace, but the numbers I am getting are higher than I expected (~$2000 installed). Are there any other alternatives to consider? One friend suggested baseboard heating, but I don't know much about those systems. Any suggestions would be appreciated.

The room is on a slab and is roughly 11' x 18' with a 7'-8' ceiling. Ive replaced the louvered glass windows with casements and will be insulating the walls and celing after I redo the electric.

I just had a 3 season room built this year. I added a combination thru the wall air conditioner/heat pump. I can't really tell yet how it will work out in sub 32 degree weather but it does take the chill off when it's fortyish outside. Mine is 10,000 BTU but they do have larger models, if needed.

Can you give me any details about the unit? Such as brand, type, where you purchased it and general cost. I thought of the Window AC unit for summer but wasn't aware you could have heat from the same unit. Thanks for the reply.

Here is what I have. Note that the price does not include the thru the wall box. This must be purchased separatly, as I learned the hard way. The box is about $ 60 from GE. You will need to run a 220V line for the A/C - heat pump.

Note: The vendor listed does not stock these in store. They must be ordered on line. Check local dealers in your area for similar units if you prefer to buy from a local dealer.

www.homedepot.com

Enter air conditioner in search area.

Thanks a lot. I'll look into that.