Quote from: scdl2018 on May 08, 2018, 09:38:59 AM

5. After the chargeback period (I have to research what this is, but let's assume 60 days for now)

As far as I've seen, Paypal can be charged back up to 180 days later.

Hypothetical scenarios:
1. After 180 days, the exchange rate is the same, no charge back happened, multisig pays you your Bitcoin, all good.
2. After 180 days, Bitcoin went up five-fold, no matter what the seller thinks about this, either seller or multisig #3 will sign, and you get your Bitcoin. All good.
3. After 170 days, Bitcoin dropped 80%, and your 500$ in Bitcoin is worth only 100$. You don't want to take a 400$ loss, and charge back through Paypal. Seller complains, multisig #3 sends the funds back to seller, but seller lost 400$ anyway. NOT good.

In this setup, you don't have any risk of ending up with a worse exchange rate, but there's still a risk for the seller. I can't think of any way to prevent this though. Thoughts?

Quote from: scdl2018 on May 08, 2018, 09:38:59 AM

I want to buy BTC with Paypal. ~ I plan a long term partnership to do recurrent deals in the region of 500$ a month.

Serious question: why? There are better and more trusted ways to buy Bitcoin.