Regarding the freshness of the house: Depending on where you are, you may have to keep the a/c going as if you still lived there. other ideas: if you have an attic fan, put it on a timer and keep it going for several hours daily. If humidity is a problem, keep that dehumidifier going. The temperature and humidity in the house should be as welcoming as if you still lived there. Also, disinfect the garbage disposal with vinegar.

If that was the only potential buyer to mention the basement I wouldn’t worry about it. Sometimes people need to be able to end the conversation quickly and using the basement as an excuse is a good way to do so.

Agree with maddielee.

Sometimes the stated objection is real and sometimes it is an excuse.

• Check with your agent to see if the MLS in your area has a place to upload documents - warranties, Sellers Disclosures, repair paperwork etc. The agent has the ability to make that paperwork private so that only other agents can see it and download for their buyers to review. This is a very helpful section in the MLS for detailed data/paperwork for the house.
• Another idea is to have a copy of the repair paperwork closer to the actual item repaired. In this case in the basement on a table where it is visible (with a sign if not readily visible) If its in the dining room, it may be overlooked or if reviewed, promptly forgotten.
• To remove the musty smell do as Lisa suggests. Then use baking soda or vinegar or even charcoal to absorb the odors. https://www.realtor.com/advice/home-improvement/old-house-smell-removal-whats-causing-get-rid/
• https://www.organiclesson.com/get-rid-old-house-smell/

Sorry to say, if I found repairs like that in the basement of any house I was looking at, I'd run. I know it's repaired and stabilized, but it's still very off-putting.

Is there any way to mask the evidence? Build out the walls with studs and drywall to "hide" the repairs? Of course, you'd still have to disclose the issue.

I already have vinegar and baking soda in discrete areas around the house. And a dehumidifier running in the basement, that reads between 45-65% when I check it periodically. The furnace runs from 10a-5p daily at 70 degrees, 60* the rest of the time. Will switch over to AC when the weather merits it.

Hot Rod: This is a low overhead basement with a sloped floor, so framed out walls aren't really a fit for the 100-year-old house. It's a $78K house, so no expectations of high-end perfection.

I do get that some people would run from this. It is the first mention we've had out of 6 showings, so I guess I'll try not to overreact. But we can attach the warranty info to one of the plates in the basement.

Good point, NC. I have a cup of each in the cabinet under the kitchen sink (why does that smell musty?) and similar on a basement shelving unit holding a lot of paint, mixed in amongst the various cans and bottles of potions. So I doubt anyone has noticed them.

The dehumidifier, well, that's unavoidable. We ran it in the basement even when we lived there.

I would lower the dehumidifier even more but start looking for areas that are moldy. Set that high in this area would allow mold/mildew to form.