I am going to buy DD a highchair in the next fe...

I am going to buy DD a highchair in the next few days because her nana kindly gave us some money to buy her one after i told her we didn't yet have one. So my question is, what do i need to look for? What is important? what do you like or dislike about yours and what is a reasonable price? sorry for all the questions but i have no idea what i should get and what features are important.