When you're looking for your first home, many buyers love the vintage charm of older houses that just doesn't come with newer-construction homes. If your realtor is showing you some homes that are several decades (or even a century) old, here are some things to look for before you make an offer. 

1. Wall Quality

Many old houses had walls that were made from plaster. Over time, the plaster in the walls can begin to crumble. Old homes also have had many decades of cosmetic "upgrades", including wallpaper and paneling. These two finishes can hold crumbling plaster in place. However, you can still feel the walls and the areas where the plaster is wearing down will feel soft and spongy, instead of nicely firm. It is especially important to make sure that you know the wallpaper is there; in some cases, there can be decades of paint over top of older wall paper, just because the removal process was too difficult for a previous homeowner to bother with. 

If the walls are crumbly behind the finishes, just know you might have to deal with re-plastering the walls or replacing them with more modern material, like sheetrock. 

2. Foundation Type

Older houses were built and varying styles of foundations, and generally if the house is still standing straight and tall, this is a sign the foundation was well-built and will continue to serve you well. However, it's important to note that some types of foundations well require a little extra attention. Old-style brick foundations, for example, may need to be repointed and sealed, especially in areas with a high water table. When you look at the basement of your old home, take a look at the walls in the basement and see if the mortar is visible. If it is sandy and lose, this is a sign the bricks will need to be refinished.

3. Older windows.

Old windows are a source of charm in an old house, but they can also be a headache. Over the years, many windows may have been fully replaced in the house, but if older ones remain, try opening them to be sure they still work. In some cases, a previous owner could have painted the windows closed, which can be difficult later if you need the windows open or if you hope to refinish the moldings surrounding the window (a proper paint job means painting the windows when open so they are sealed shut). 

These may seem like small issues, but replacing painted shut windows, repointed basement bricks, and refinishing walls can become costly. Be sure to ask your realtor about the details of the home before you sign a legally-binding offer.