Bhutson
Hi, welcome to the forums!
They can charge for court fees, which shouldn't be much more than the original debt. Sometimes the judge will give you a break on the amount they're actually trying to collect for, if they find in favor of the collection company/law firm.. They cannot continue to add on interest.
Is this your first contact with LVNV Funding? How did you receive the summons? If this debt they are trying to collect on was listed on your bankruptcy, then you may owe nothing.
Please keep us informed on this.
Mike