Buying 50+ years old houses for buy and hold

[Mary Jay]

I have an old house (built in 1920) and two homes built in 1998 and 2003 (I think)

Never had any issues with any houses. I did have to put a new roof on an old house though because I was worried it may start leaking, and it cost me 2K...

Other than that no problems.

But, despite my good luck with my "old-ie" I have always been scared to buy old houses (By old I mean 50+ years old).

I thought I should focus on buy and holds that are less than 30 years old and cost around 100K and rent for 800$-1K...

But lately Ive been seeing a lot of people doing 30-50K older houses and rent them for 500-700$

1) What do you guys think? What is better?

2) Someone I know buys 30K houses and redoes plumbing, electrical, etc which will be another 20-30K and then he rents them for 700$...My concern is, when you buy a house that is that old, it is probably possible that the rehab may be around 100K, not 20-30K....Even if a house does require 20-30K rehab such as electrical, plumbing, etc, what are the chances that structurally its good and sound? Plus foundation....I don;t know...

What are your thoughts?