Actually salt water is much easier than ya think.
I've had 30 gal, 55 gal, 125 gal & 180 gal salts over the last 10+ yrs.
The expense is in the fish definitely, if you go reef, the live rock. The equipment (protien skimmer, sump, good lights) can be expensive (although I make a lot of my own gear so it's much cheaper that way).
Timewise, it's not as time consuming as ya think. If ya know how to setup the environment, then ya do zero water changes, zero gravel cleaning, zero adding salt (salt doesn't evaporate). You feed once every 2 days, top up with fresh water once every 2 weeks or so (bit more in winter due to dry air).
I sunk a 180 gallon salt water tank into my living room wall a few years ago, that was a challenge.
