I can add CFW(Custom firmware) to your 3ds for 40$, and I can add additional things for extra
What modding your 3ds can do
-UNLIMTED FREE 3DS GAMES!!!:0
-Custom backgrounds and themes
-emulate some old games
-There's more but I haven't dabbled in stuff outside the first 3
I can mod any model except DS/DSI, I could try to mod them but I have never attempted to.
What I need from you
-Your console
-SD card preferably 16gb and above if you want alot of games
*IMPORTANT*
There is a chance your console could brick during the modding process, it's very unlikely to happen as it has not happened through all my time modding console. I could try to fix it but it's challenging, just putting this disclaimer so that you know the small risk.