We love our old mid century charmer (and by "old," we mean 1964, which really isn't that old in house years). We appreciate the original elements, and are trying to stay true to its personality. However, there are pros and cons to old homes. Things can be out of date; there are occasional "surprises;" and unpredictable expenses.
Fireplaces freak me out. We built our first time, and installed a huge, gas fireplace with built in shelving and shiplap. We used it ONCE in 18 months of living there. Ridiculous, I know. I just never quite got the hang of it, and it stressed me out. Our new home has a brick, wood burning fireplace. It's gorgeous. I want to use it all winter long. So, I called a local chimney sweep to come and clean the chimney. They suggested that they also perform a "video tour" of interior of the chimney, to make sure that everything is up to date and that there is nothing dangerous that could cause a fire. The cost for the chimney inspection and cleaning was $269. We used Midtown Sweeps.
This certainly may not pertain to you, but our house is located in the woods, and was vacant for 6 months; so we had a spider problem. Oh, and I am TERRIFIED of spiders, diagnosable arachnophobic (if you've watched my insta stories, you know I was bit by a Brown Recluse!). No way I moving into this house without 100% assurance that it was spider-free. I hired a local pest control company, Griffin Pest Control, that had been recommended. They came to the house and treated the entire interior and exterior, including the basement, garage, soffits, roof, and attic (they said that performing this treatment mid renovation was perfect because it allowed them to reach areas that they typically cannot when cabinets are installed). The original treatment cost $143. They will return every 3 months for additional treatments, at $111 each. This the "gold" treatment, and I wanted the best of the best. They also offer free callbacks should we ever notice any spider activity in the meantime. I told them they might regret this offer, and that they were going to be #1 on my speed dial.
If you are moving to the country, or any area where a home has well water rather than city water, you will likely get a well inspection before closing on the home (required protocol), but they typically only inspect the actually well buried in the yard, rather than the tank and pump (that are typically in the basement or utility room). We had someone come inspect our tank and pump. The inspection was free. They did tell us that our tank was getting old, and would need replacement in a couple of years. We decided to replace it right away, rather than risking issues down the road. The new tank with labor cost $700.
Like the well, it is required that you have a septic inspection before closing on a home. However, septic tanks need to be cleaned every few years. Since we did not know the history of the home, we ordered a cleaning. We had two "lids" that had already been dug up but to the inspectoin (you can see the two dirt piles in the yard in the image below - if they have to dig, it will cost a little more). It cost $400 to have both cleaned.
Old electrical can be scary. Eric, our wonderful electrician, inspected our existing electrical, while switching out a few fixtures and updating a few things around the home. I don't have an exact cost for "just" an inspection as we got a blanket price for everything that needed to be done. I would certainly recommend that you ensure that your electrical is up to date.
Hope you find this helpful!