alter table invoice_items add taxable tinyint(3) unsigned not null default 0 after cost;

update invoice_items set taxable = 1;

alter table invoices drop column postage_tax_cost;
alter table invoices drop column item_tax_cost;
alter table invoices change fulfillment_tax_cost fulfillment_taxable tinyint(3) unsigned not null default 0;
alter table invoices change shipping_tax_cost shipping_taxable tinyint(3) unsigned not null default 0;

update invoices set fulfillment_taxable = 1, shipping_taxable = 1;

alter table jobs add closed_date datetime null after closed;