second instrument ???!?!!?!!

gang i REALLY wanna get a second instrument...

i either wanna do tuba or french horn

tuba because 1, my brother plays it so we have one in the basement and it's in bass clef (i play trombone) so i dont have to learn treble clef

french horn because it sounds SOO BEAUTIFULLL <33 I LOVE IT ITS SO WARM SOUNDING AND ETHEREAL

issues with tuba are i don't have my own mouthpiece nor do i have the money for it and i will probably have to teach myself (maybe with the help of my brother or father)

i also have the option of, instead of tuba, i could simply do bass trombone just to stay true to my origins

issues with french horn is i will have to buy myself the entire instrument, which i TOTALLY dont have the money for, i would have to learn totally solo (even my band teacher is quite unfamiliar with the horn), and the mouthpiece is so small !!!!!!!! like a fourth the size of a trombone mouthpiece !!!!

chat pls help !!!! @_@