How to prevent excess summary traffic by customers so i don't get left with the bill?

I have a customer whos site is using 30+ gig bw per month.
Its looking like there site will cause me to pay excess fees to JH @$2.50/gb because it will push me above 60 gb/m.
Thats all ok, but if the customer decides at the end of the month to skip out and not pay their excess bandwith fees to me i will be left carrying the bag.
Is there any way to disallow customers from exceeding there bandwidth quota(plan uses summary quotas), because currently hsphere allows to run up excess above set quotas?

Re: How to prevent excess summary traffic by customers so i don’t get left with the b

you can restrict user by applying hard limit on any particular resource and this can be done on plan level,
i.e. all users under this plan will be affected.
To achieve this, please follow these instructions. Here you can apply limit on http/ftp/mail traffic.
Also please confirm if this is what you are looking for.

Re: How to prevent excess summary traffic by customers so i don’t get left with the b

You may also want to look at:
Settings → Notifications → User Warnings

in reseller admin CP

Re: How to prevent excess summary traffic by customers so i don’t get left with the b

Thanx Deepak. This one’s an HSphere anomaly…if you set a plan at 20GB max limit it doesn’t prevent using above that limit, it is the limit that a user can pre-purchase to…however i don’t see anyway a user can pre-purchase extra rescources in hsphere or why a reseller would set a plan limit of 20gb but only advertise for eg. a 15gb max, when a user can easily increase their limit to the plans max value at any time without cost by clicking the “change traffic limit” in the left Statistics menu. Thats the way i read it anyway…lol another half-assed hsphere thing.

Thanx Tanmaya. Looks like this is the option.

Cheers