The answer is breakers. There are houses in St. Paul that still have old electrical boxes with fuses instead of breakers. Fuses seem to work fine but those boxes are at least 50 years old and some are much older. Having an ancient electrical system means having fewer circuits. Insurance companies do not like fuses and will charge more or they won’t provide insurance at all.
If the power is 100 amp and the fuse box does not have to be relocated prices for upgrading to breakers start at about $1500.00. It can cost twice as much if there is 60 AMP service or if the electrical box needs to be relocated. It is easy enough to get an estimate from an electrician.
If you are buying a house with fuses plan on upgrading to breakers. Make sure to check the electrical box before making an offer on a house. Sometimes there is more than one box especially if there is central air or an upgraded kitchen.
I strongly encourage sellers to upgrade to breakers before they put the house on the market.
We use our houses much differently today than we did in the 1950’s. We use a lot more electricity. I have seen old fuse boxes with four or five circuits for the whole house. Newer electrical systems will include that many circuits just for the kitchen.