There are lots of differences between the two - different keywork & fingering systems; there is a double reed on bassoon rather than single reed/mouthpiece comination. It all takes a bit of getting used to - some people find it easier than others. The ability to read bass clef music is also an advantage. My number one reccommendation is to find a good teacher - you will progress quicker & are less likely to get into bad habits!
Regarding an instrument - a decent instrument for $500 is asking the impossible. New the cheapest Far Eastern made ones are $2,000 or more & most of them I wouldn't touch. Over the years thay have improved but are still not good & the older ones really dire.There is a lot of rubbish out there & the costs of getting a bassoon put in playing order can be in excess of $500. Look for a recognised brand like Fox. If you find a teacher he/she should be able to guide you & suggest a suitable bassoon.
Good luck in your hunt & enjoy playing the best instrument if you do get one.
Re: Clarinet to bassoon 00:36 on Monday, August 17, 2015