Removing Unknowns

We want to put on a Ring doorbell (among other things) on our house.Our present doorbell is a wireless one that I added on after we moved; our house predates electricity so we didn't have a doorbell circuit that drove an actual doorbell. We do have a switch right next to the front door that controls the light above the porch.Drilling into the front trim boards around the front door isn't something that I was looking forward to. It's one of the reasons we decided to call a professional electrician.Then we got the quote... nearly $3000. Of that around $700 for the front door.Looking downstairs under the porch (yaay for access to that!) I was able to see the run of wire that feeds the front light. Once I see the wire there, I can start to formulate a plan.I think I'm going to tackle this myself. Here's the steps I'm thinking of:

1. Disconnect the wire from the front switch
2. Attach a pull cord to the wiring (for later)
3. Pull the wire down into the porch crawlspace
   1. This gives me enough margin to add an electrical box without trying to stretch things too much
4. Pull new wire (using the pull cord) down to the crawlspace.
5. Add a junction box to the crawlspace.

Once I have a good source of 120V I can go and attach the 120VAC -> 30VAC transformer for the Ring doorbell.From here I just need to drill an oblique hole into the stud-space near the front door light to be able to pull the doorbell wire.Done deal.It's all about knowing what I'm getting into.