Options for upgrading baseboard heating

[Ross Leavitt]

We just bought a duplex near Corvallis, Oregon that we are remodeling to rent out. Both sides have baseboard heaters (as far as I can tell, they are original from the 50s), and they need to go. What would you all put in their place? Each side is 3 bed, 1 bath.

My initial choice is cadet heaters. My electrician said they would be about $400 each, installed, and I will need six per side. For that price, each unit will simply have a dial on the unit rather than a separately-wired thermostat. 

It seems like a lot of money to spend on a low-end heating system, but the other options don't sound good either. Ductless is more expensive but much more desirable, but I'm concerned that the tenants won't be diligent about cleaning the filter and it won't last as long as it should. What has your experience been with ductless units in rentals? Also, I think for a 3-bedroom I will need some cadets anyway to supplement the heating.

Are there any other options I should consider? Thanks so much for your advice!