i am looking at various ar-15 rifles to purchase right now. There is one manufactured by olympic arms called the GI carbine. It has an A1 sight. My questions are is it a good price at $650 dollars. Is it an specimen worth having for the price? Can you upgrade the A1 sight to A2 sight  on the rifle? OR i have been looking at DPMS arms. Some of those look kinda cheap though. So i guess im saying that i need some helping finding an affordable ar-15 Thank you for any help that can be had.

Welcome aboard!

Oly and DPMS both make quality rifles.  You can expect to spend as little as $600 on one or up to as much as you want.  There are many different options for these things and the cost varies based on those.

As for the sight, you can pretty much upgrade/change any AR sight.  Shouldn't be a problem

Also, you posted this in the wrong forum so expect a talking to by a sysadmin.

thank you for the reply. I hope i dont get chewed on too much for my post. I realize my one question kinda spread into a questionarre. So even if i bought an AR15 that didnt have a removable carrying handle i can still change out the A1 sight for the A2 sight? more more thing how much does an A2 sight cost roughly? Is the installation straightforward or complicated?

I wouldn't bother getting a fixed carrying handle.  I would get a flat top model with Flip up front and rear sights.  Unless you just plan on using iron sights.  THe flat top model is so much more versatile.  Also check out Rock River Arms.