No matter what hosting company, (not just Yahoo!), how long after the domain expires can I buy the domain?

Reguardless of the hosting company, how long after the domain expires from a previous owner, asuming that there are no backorders or otherwise ownership of the domain after expiration, can the domain be purchased.

I have been trying to buy a domain that expired on the 27th of april, but I still can't buy the domain. The WHOIS database, on multiple company websites, says that domain

After the domain expires, there is a grace period during which the original registrant can recover the domain for a hefty fee. In the past, grace periods used to vary a lot, but now it's become standard at 35 days.

True domain dropping from the registry can take up to 5 days, so expired domains become available in 35-40 days after expiration.

The best way to know exactly when expired domains are released is by checking definitive domain dropping lists.

These lists are available 3-4 days before the expected dropping date, and are FREE and publicly available in sites such as http://www.vztools.com.

If the domain is very desirable, chances are that it is backordered already, so you must backorder it too (and likely get into an auction with other bidders), rather than just waiting it to drop.

If you can afford losing it, just wait for the next day after the expected drop date, rather than the same day, because you don't really know what time it is going to be dropped, and many failed trials to register it might tip other people about the domains' desirability.