Yes, u can open an account in Sing, even Maybank2u can let u do that easily. But, the best is open bank ac directly at USA. It's not true that paypal do ip check, all person can access. Alternative such as Moneybookers is good coz reduce bank wire transfer fee. But most Ebay buyer like paypal very much. If u tell them to pay through ikobo, u and they will face problem.
IKOBO is highly prevent fraud, so when they wanna send money through ikobo, they need to fax their personal details to ikobo to verify themselves first before they can upload fund to ikobo, and this process take a few days. Ikobo's customer service oso not good. When u wanna receive money, u oso need to verify yourself at ikobo by submitting your details through fax to ikobo(usa). If u didn't do these step, u will find the difficulties.
paysystem and 2checkout is ok, it can help u to collect fund. After that send check or wire to u.
Hope my info useful for u.
Ecommerce Expert