well don't do them straight away of course.
what i did was caught swamp lizards til about lvl 64 and then started on graahks and was doing invents in 20-30 min so was around 500-700k p/hr
You should be level 80+.
earn money from stuff
you should train on somthing around your level and gives fair drops
It shoud be 500 millstone or higher
The higher the level the more profit you should be able to make.
Level 80+
I would say you should be level 50+. You could be lower but with better food.
Depends on if you pot your skills or the weapon you have and your strength level.
You should train on Range.
Yo momas house
level 138. there is no higher level on runescape (for players)
I say whenever your prepared, but if your not sure, level 100 will be fine.