I have been watching a domain name for a while and I believe the owners are not going to renew it. It expires next monday will I be able to buy it then?

Unfortunately, no.
Domains normally go through a grace period, designated by the registrar, after the listed expiration date.
Then, you have to wait for the name to officially drop from the ICANN database before it will be available
for registration. Usually, you can place the name on back-order before then, but that is not guaranteed.
You just have to keep a close eye on it during that time.

Anyone recall hotmail.co.uk...?

Some old geezer from the UK bought it as Microsoft neglegted to renew and did he charge them...? No. He gave it to them for free.

What a story that would have made...

hahaha...that is very funny. He would have lost it anyways though. I'm sure hotmail is trademarked.

I have been watching a domain name for a while and I believe the owners are not going to renew it. It expires next monday will I be able to buy it then?

I think that about fourtnight it won't be availible for the registration. And sometimes such domain names are in lists for auction

its takes around 3 months more

No, there is something like a 90 day drop period were they can still re-new it