you can go to ebay to see what you might get if you sell it. as far as the tab 10.5, go go amazon.com and read the reviews and specs there - that is what I do. Usually I will disregard the real bad and real good ones.
Just a couple of comments.
First of all
I have a samsung tablet (galaxy note) and use it all the time. It is basically the same as a tab but cost more and has a stylus so I can take notes on it. I will not have an apple at this time because of the lack of a microsd card.
If you have a lot of apps you paid for from the apple store, you may want to consider getting another ipad. they do have better security so if you are worry about your personal privacy, then stick with apple. The one thing it does not have is storage, unless you want to pay a premium.
as far as the tab, As long as you only get apps from the google play store, your security should be okay. You can do a lot more with a Tab than you can with an Ipad. You can store a lot more on a Tab because of the microsd card feature. you can add at least 64 gigs (maybe 12
of storage space to your tab which could come in handy if you have a lot of videos or music that is played when on the go.
It is a tough choice - good luck