Urgent help needed with hair extensions?

hi,i am due to marry in 3 wks time and im having hair extensions put in proffesionally,im worried cos i dont know nothing about these,i have short blk hair around 6 in long.the hair dresser tells me that she is going to braid them in with my natural hair then leave the rest long and curley,she tells me that she is going to use synthetic sleek hair,she says its very good shes charging me �200 does this sound about right?i wanted her to use 100per cent human hair but she tells me that it would cost hundreds of pounds but ive seen human hair for as little as �16 per packet so i carnt see what the problem is,can anyone please advise me also im used to having a fringe,she tells me she could either braid it in,thats what i dont want or leave it out straight which i think would look silly,any ideas,replies really appriated thank you.