450 is your way to go man, it can lift good enough payload and mounting a yi cam will also be easy...
if u want to face the problem of programming and tuning your quad to stay stable then 250 is your cup of tea... plus u can flip easily and all...
i got my 250 class for 15030 as i ordered for 2 batteries and i had an existing charger, u can go for one battery and invest the rest in a charger...
http://www.rcbazaar.com/product.aspx?productid=992http://www.rcbazaar.com/product.aspx?productid=2011http://www.rcbazaar.com/product.aspx?productid=4733http://www.rcbazaar.com/product.aspx?productid=2467Just to clear this up, u cannot expect this hobby to be cheap.... it is a little expensive... especially the multirotor side! a lot of people in this post have already given up as u want the cheapest deals but aren't ready to accept that it is cheap... going cheap in this hobby can turn out to be even more expensive than you think... i fried my FC and RX just to go cheap and i got a bill worth 3k... just know what you are doing and take the help of people in this forum on this subject. it's always best to build with a person who knows what they are doing so they can teach you in places where you go wrong... if u still don't think it is cheap enough you are on your own and you can do your own research and get the "best" bang for the buck. People have suggested enough in this post and its your turn to make a call...