about US $500 limit for single or multiple transactions.
I think it will be implemented by software and applicable to both type of transactions. For example, since feb 2010, personal payments are not allowed to and from India so if any non Indian paypal user wants to send personal payments to Indian paypal user then he gets a warning from paypal - Personal payments are not allowed to the paypal users in India.
Similarly, from 1st march, if we request more than $500 (either for single or multiple purchases) then Paypal itself release a warning and we will not be able to send an invoice if total is more than $500 (and i am sure this limit is applicable to Item price + shipping). So if you list any BIN item with $50 shipping, you have to keep its price less than $450 if you are using paypal.
Similarly, if some buyer purchases 15 items (say avg cost $40 and shipping is free) from single seller then he will not be able to pay $600 through paypal in a single payment and whenever he will try to pay using ebay / paypal check out he will get a warning (like you can not send this amount to this seller blah blah).
Multiple BIN items less than $500 will be no problem - just write new paypal rule in your auction and request buyer that he has to make multiple payments if total is more than $500 for multiple purchases (30 cent loss for sellers for each payment). But problem is BIN item/s more than $500 (single item) and auction item/s which have probability of getting more than $500 (single item). Suppose i am expecting $400 for any auction item listed at initial price of $100 and i have only paypal as payment option. But if this item gets $700 then what will happen? Just ask buyer to send $500 only through paypal (result a very happy buyer) OR say i can not accept $700 through paypal so send me 2 payments of $500 and $200 (most buyers will not feel comfortable doing it and find it suspicious.. result International buyers will lose trust on Indian sellers. It is also violation of RBI law where seller has done some Jugaad to receive more than $500 for single transaction). Even if you quote this 2 payments thing in your auction description, many buyers will hesitate to bid on your auction. It also increases the chance of getting negative feedback as buyer will not be able to complete check out through ebay. Same reason can be given, why international buyers find Paisapay uncomfortable and prefers paypal only.
The only legal way to sell more than $500 item on ebay is write clearly in your auction - paypal is not available for single item listed for $500 or more. Request bankwire / cashier's check etc (whatever you can accept). No paypal offered means 90% buyers will not take interest in your items.
thanks
Hasy