what should i do?

teacher asked me whether i wanna take adv foun exam this year.
this is also something i am thinking.

if i take it this year, it's 50/50 for me to pass.
then i might need to take gaynor pointe shoes which will cost 300++. where the normal price for the other brand is only 100++.
wat if i fail? the exam fees isnt cheap too. it cost 200++. haiz.
if i take it this year, i will need to put ALOT more effort. but can i make it?

if i take next year, then the chances for me to pass will be higher(i think so). but then i am worrying. if i take it next year, at this moment, i will be having practical training. i might not having so many time to have more classes. n if i am not improving, maybe just maintain or it get worse? then i am just wasting my 1 yaer. n if i take the exam next year, then i will need to pay for another year fees.

so how? gonna tell teacher my decision later. i think i will choose to take adv foun next year. n start having grade 8 classes next month.
am i making the right choice? tell me!!!