Rehab on a 1920's house

[Nick Seginowich]

I recently found a 2100sqft, single family home built in 1925, in a great area with some really good numbers. I'm just a little unsure of the rehab as it should need a fairly extensive one. I'm working with a contractor I haven't met before but was referred to me by my realtor and he thinks the rehab should be around 30k just at first look, and if we can do it for 30k I would be pumped! But, with a 1920's house I feel like their might be some really expensive unexpected repairs such as, old plumbing, electrical, sewer line etc... I'm wondering if anyone has some insight into what I should look for and possibly what is a common hassle for a house built in the 20's? Also, this would be my first deal. BTW i'm still deciding between making this a BRRRR deal or just a flip.

Thanks!