Getting nervous about cost of engine rebuild.

This will be the first time I have ever had someone else rebuild an engine for me and I am getting a little nervous that it could be more than expected. The engine is a small block.

They are turning the crank, balancing the engine, porting the heads, installing new springs, and using a set of old Chrysler adjustable rockers. The cam is $450 and is the only major new part they will be installing. I am figuring around 4-5k.

$1000 machine work
$1500 in parts
$2000 to have the engine assembled

The engine was not bored out, acid dipped, sonic tested. I am going with $1500 for parts because of all the random small things that add up. Does anyone see any reason that this engine would be well over the 5,000 point?
I don't know how mechanically inclined you are but you could possibly assemble the engine yourself.