Currently I have 40.20m gold in my 2nd account (Rogue) and idk if it’s now good for mythstone conversion…so I can build my own mythic item and as I did a 
some say dealer perk is the way for obtaining a lotta gold for selling out unwanted items…and my gold find rate is up to the max cap (650% and 1000+% if I opened up a legend map)
(I will do the same on my main account warrior which gold is 32.1m)
I play the game before but my knowledge in that time is a bit smaller…not until I tried out PvP and then payed a visit here in this forum…
Farm more i suggest. Specially if you will be building up mythics. You have to add legend affixes as well.
Already stocking up some legend crystals by converting repeated drop of eternal items…and so the common crystals
to give you an idea of how much Gold you need:
2 Hero Mythstones to 1 Mentor is 500 Gold.
1 Mentor to 1 Hero is 1000 Gold.
2 Time Mythstones to 1 Master is 550,000 Gold
1 Master to 1 Time is 850,000 Gold.
Gold Find improves Gold drops
Item Drop improves Gold drops
Fortunate Perk improves Gold drops
Hound Pet can find buried Gold drops
Dealer Perk - sell Items for 10x Gold
Luck - chance for Items to be found with higher Tier up to Legend
Higher Tier Items sell for more Gold than lower Tier Items
Higher level Items sell for more Gold than lower level Items