The depreciation amounts on the Book Value report when compared to the General Ledger report (or Balance Sheet) may not match for the following reason:

The General Ledger report only uses Post Dates while the Book Value Report works off of in Service Dates. If these relative dates fall into different ranges, or more records are being included in one report than the other, the reports will not match.

To more directly reconcile Fixed Assets to the General Ledger, we recommend using the Account Distribution Report:

To set up the report:
1. In Reports > Transaction Reports, create a new Account Distribution report
2. On the General Tab, select detail and set the post date to the same time frame used in the General Ledger report. Leave all other date fields to include all dates.
3. On the filters tab, select Accounts and filter on the same accounts in the General Ledger report
4. On the filter tab, select Post Status and filter either to only include Posted (or Posted and Not Yet Posted if you are including Not Yet Posted items in your General Ledger report. We would recommend setting both to only include posted items initially).

To Compare the reports: 
On the Account Distribution report, subtract the Total Debits from the Total Credits to get the net change for that time frame. Compare that total to the Account Net Change on the General Ledger Report.