Estimating rehab costs

[Melissa Denton]

I have my first wholesale deal under contract.  It’s a 3 bed/2 bath 1776 sq ft Victorian. It has already had some  work done and the house is solid with many of the original features intact. 
All of the construction materials that have not been installed stay with the house. This is tile, mortar, and grout for the kitchen area and bathrooms.  The kitchen has already been prepped for the tile so all that is left is to install it.  All of the new cabinets are there, but have not been installed. Kitchen appliances are a new cooktop and dishwasher.  The house still has the original wood flooring and the wood from the kitchen was salvaged to repair other parts of the house, so there would not be hunting for wood and matching varnish.  90-95% of the plumbing and electrical have been replaced, including a new breaker box.  The water heater is also new.  The HVAC has been completely revamped to provide central AC and heat throughout the home. All of the windows have been replaced with the exception of a large picture window in the kitchen. They have installed new ceiling fans.  They have installed recessed lighting in th kitchen.  

There is still a lot to be done, but most of it is cosmetic.  Drywall in a few places, new paint and so on.  The counters need to be added, a kitchen sink, oven and fridge need to be installed.  Both bathrooms need flooring, toilets, vanities, sinks, mirrors and bathtubs or showers.

I researched costs and came up with 30-45k to finish the house.  People are telling me that I am too low.  Where am I off?