It depends on how long you're staying in the house. If you intend to live there a long time, make the house work for you. You'll get much more value out of that than any notional loss you might eventually suffer during sale. But if you intend to move in the next 5 years, the best idea would be to talk with a real estate agent familiar with your market. They'll know what kind of hit you might take.

Is there any way to add to the laundry room without totally eliminating the bedroom?

Unfortunately, no.

Speaking just for myself, I would definitely do something like that. Three bedrooms is very common. I’d be surprised if it literally ruined the value of your home.

An easy way to get an idea is to look at current listings in your area. What are typical 3 and 4 bedroom homes going for?

If most homes in the neighborhood have 4 bedrooms, then you will lose value on resale. Everyone will like the large laundry room though.

Ask a local appraiser or real estate agent to do an appraisal with & without bedroom to know in confidence.

Usually when a house is listed marketed comparables CMAs are done to like homes in the nearby neighborhoods.

Could technically lose value when a room is lost,however it's not to say it will prevent it from selling to the right buyer for the same price. But be prepared to possibly lose some.

First, I’m not a realtor, but I am a real estate investor. It does depend on your market and neighborhood. A three bedroom/2 bath home is usually the highest in demand. However, your neighborhood may be different. It may lower your selling price, nonetheless.