shopitembuying

When you own a shop, as well as selecting goods that the shop will sell
you can also set rules regarding what items the shop will purchase from other
people.  This is achieved via "manage set".  There are 3 variables you may 
set, buybal, maxbuy and buyratio.

Buybal stands for the buying balance.  This is a fund that is transferred
from the the shop's bank and used to purchase items.  Once the fund is empty
then no more items will be purchased.  Example of usage
The shop bank currently has 500000 gold coins and the buying balance is
currently 0, you type "manage set buybal 100000".  This will transfer 100000
to the buying balance from the shop bank.  If you then set the buying balance
again to a value lower than 100000, then money will be transfered back into
the shop's bank.  For example "manage set buybal 60000", will place 40000
back in the shop bank.
If you set this value to 0, then the shop will not purchase anything.

Maxbuy stands for maximum buying price.  Given that the value of items can
vary greatly, it is possible to specify a maximum the shop will pay for an
item.  For example, "manage set maxbuy 50000", which make the shop pay no
more than 50000 for an item.
If you set this value to 0, then the shop will not purchase anything.

Buyratio is the percentage of an item's true value that the shop will pay.
The buyratio can be a value between 50 and 100.  For example
"manage set buyratio 50" tells the shop to offer 50% of an item's true
value (presuming that value does not exceed what maxbuy is set to) when
purchasing it.