Taxes on purchases

[Ricardo Chavez <ri...@gmail.com>]

Hello everybody. I have some doubts about how to handle taxes on purchases.
I need to keep track of the sales tax paid when I purchase something from a
supplier, as it needs to go to a specific account (say, 'sales tax paid').
Here in Peru suppliers must indicate if their prices include the sales tax
or not. If the price doesn't include sales tax, there is no problem: an
invoice item of type Invoice Sales Tax can be added before approving the
invoice so the correct accounting transaction is made when posting the
invoice to the GL. The problems arise when the tax is included in the price.
I tried handling this by changing the price to the real price (ie. the price
minus the sales tax) in the Receive Inventory screen, but it that case it is
considered as a variation of the purchase price, and so a new entry to the
Purchase Price Variance account is added to the transaction, which is not
what I want.

Roughly speaking, this is what I want to achieve:
(for price=100 + tax=10 = total=110)
Debit Uninvoiced Shipment Receipts for 100 and our 'sales tax paid' account
for 10
Credit Accounts Payable for 110
When the tax is not included in the price, this can easily be done with a
manually added invoice sales tax item. My question is: is there any way to
handle the case when the tax is included in the price without messing with
the code?
Thanks in advance.

-- Ricardo Chavez