13k hp at lvl 175

is that enough to have 13k on bow master on lvl 175 to boss most of bosses with/without hb?

 

yes, there is only 3-4 bosses u cant do without HB depending on your skill and luck.

If you want to be independent of HB, you need around 15.8, 16.5 or 19k depending on the boss

 

which bosses are those bosses? toad ,the boss,auf?

 

Toad most definitely need 16.5+k hp
Auf can be done with as little as 9.5k hp if you position correctly and don't get extremely unlucky, but 19k will make it braindead (survive two hadouken blasts under sed). Additional HP helps you play a bit greedier for more damage in royal guard and auf.
The boss, need like 17k I think, but if your party rotates holy shield on time, don't need to worry about hp.
Von Leon only need 8k for damage reflect and mob touch damage, the rest you outrange and should not get hit by

Edit: I used to do auf regularly on my BM at 13k hp before I finished fully washing it. I would still recommend doing the daily hp quest until 17k ish just for extra comfort at bosses

 

+1 on that but toad hits only 15.5k on my BM, hence I stated 15.8k