As far as I know, almost all the boat rentals on the lake are around $300 for 8 hours... not a very generous price. The boats at konocti harbor are quite crappy. I'd recommend hiring a guide rather then renting from konocti/disney/ferndale.
These guys are awesome if you can call ahead and fish multiple days.
http://www.anglersadvantageinc.com/
I stayed here over spring break in the "Mallard House". Was $75 a night, kitchen/tv/internet, slept 4. Caught a ton of fish off the dock, 2 5-6lbers. They have a roomy 12 foot aluminum rowboat you can take out as well as a couple kayaks. Definitely a good option.
http://www.bellhaven.com/cottages.html
What university are you from?