private void btnAddPayment_Click(object sender, EventArgs e)
        {
            var form = new AddPayment();

            form.AddNewPayment(_contractId);
            if (form.ShowDialog(this) == DialogResult.OK)
            {
                DataAccess pa        = new DataAccess();
                var        tempContr = pa.GetContractById(_contractId);
                tempContr.NoOfInstallments = tempContr.NoOfInstallments + 1;
                txtInstallments.Text       = tempContr.NoOfInstallments.ToString();
                pa.Update();
            }
        }
        private void paymentGrid_MouseDoubleClick(object sender, MouseEventArgs e)
        {
            int payemtId = 0;

            if (paymentGrid.SelectedRows.Count > 0)
            {
                var row = paymentGrid.SelectedRows[0];
                payemtId = ((dynamic)row.DataBoundItem).Id;
            }
            var form = new AddPayment();

            form.EditPayment(payemtId);
            if (form.ShowDialog(this) == DialogResult.OK)
            {
                DataAccess pa = new DataAccess();
                paymentGrid.DataSource = pa.GetPaymentByContractId(contract.Id);

                //todo: noting
            }
        }