My broker didn't disclose in the listing that it was a foreign seller (Canada). When I found out, I was a little bit concerned after reading the FIRPTA horror stories here and on another board. In case you're not familiar, FIRPTA requires foreign sellers to pay taxes on the sale of their property upfront. If they fail to do that the IRS comes after the buyer for the taxes. I asked the escrow agent about it and she assured me she would make the proper withholdings from the sellers' proceeds. I still haven't heard from the IRS, so knock on wood. Timeline wise mine my purchase was great, however, I believe attorneys in Canada can get certified to be US compliant notaries; that may not be the case in other countries where the only US compliant notaries are in the embassy.
One specific horror story I read that sticks out in my mind is one where a buyer was stuck with all the FIRPTA related costs because the escrow company said in the contract the buyer had agreed to pay all closing costs. If you are knowingly going to make an offer to an international seller, I would say in your offer you specify they pay closing costs and offer maybe $500 or so more total, which is the normal amount for closing costs on most contracts. In my case the sellers paid closing costs even though in my initial offer (not knowing they were international sellers) I had said I would. I think they did it specifically to avoid any FIRPTA closing cost disputes. That was a nice, unexpected bonus for me. Good luck!