Ok,this is sort of where you might have to make your own judgement.
In a lot of sites I read,some said 1 leo per 10gallon.
I have 2 leos.
Each in a 10gallon.
Now other sites say juveniles in a 10gallon,adults in a 20.
I,personally,don't have much in my 10gallons.water dish,food dish,calcium dish,a hide (which is a humid hide,I actually used a container).I strongly urge adults be kept in a 20gallon.I don't think theres much room for leos in a 10.
Now a few people will disagree& that's ok.But I honestly think my leos would want more room.
After all,they'd prefer a humid hide (which will help with shedding),a hide on the cool side& a hide on the warm side.
I'll be upgrading my leos to 20's.Keeping the 10's for tarantulas.
That being said...I wouldn't advise housing more than one male together.
I would strongly NOT advise that.
Females...you can probably do that without
too much problems.
(take in consideration your leo's temperment.
When you introduce them watch closely to make sure they don't fight..as in actual fights that look like they can lead to death or serious injury.)
I personally would house 3 in a 45 gallon. 20 gallons for the first,10 for the additionals.
Hope I was of some help =]