Cutting hole in basement wall

I think I understand what you are doing. You are planning to run the new drain under the new addition, under ground, and into the existing basement of the house where it will connect to the existing drain. This will likely be a 4 inch PVC line, at least it is at my house.

I had to do something similar for a 2 inch diameter sump pump connection. I rented an electric hammer drill, put a two inch diamond core bit on it, and went through the 8 inch thick concrete wall in about 1/2 an hour. For a four inch hole, it is likely to take at least an hour, but the process is the same. The hammer drill is pretty heavy, so make sure you get one with a stand. You don't want to be holding this device up for an hour. Also, make sure you rent a bit deep enough to get through your wall.

It's a lot easier if you can arrange the plumbing to pass through the rim joist.

They do have core bits you can use. You can rent the drill for the bit and it will cut whatever size hole you need. You can probably go with a 4" bit for for a 3"PVC pipe.
Rim joist would be easier, but the distance from the wall will dictate the pitch needed and the hole location.
Ron

Bladesj,

I think what you need to do is forgo the will then and bring the plumber in now. It is foolish if you are going to have them trim the project out if the rough in is wrong and trust me they will let you know and so will their invoice to correct it!

Find a reputable plumber and talk with them now to prevent a huge headache for all later.

Also, Jogr is right if you cann go through the rim joist that is the way to go!

Don't be penny wise but pound foolish get the professional in now if you don't know how to do something find someone who does you will be money ahead in the long run.

jogr