If you search you will find literally dozens of blog postings about the pros and cons of various oscilloscopes. I'd direct you to one set in particular, there are many more out there. Go to eevblog.com. Click on the Episodes tab and search that page for "oscilloscope". You will get about 70 hits. At a minimum take a look at:
http://www.eevblog.com/2013/07/25/eevbl ... e-on-ebay/
http://www.eevblog.com/2015/01/15/eevbl ... es-review/
After viewing a few blog entries about scopes, you should have enough information to start asking yourself the right questions (analog or digital, bandwidth, number of channels, special features, price) to narrow down what you really need.
Good luck with your search.