Many of the Realtors below answered the question perfectly, get a CMA that would tell you what the difference would be. I wanted to add from a Mortgage point of view as well, first I would ask what type of home is it, I am assuming it is a condo or a townhome because of the number of bedrooms. By having that extra bath you will most likely be increasing the number of comparable homes that the appraiser will have to work with when appraising your home. In this market place one of the hard things is that so many of the comparables for homes are being bought at foreclosure prices, the larger the pool of homes in your immediate area (less than one mile away) that have sold within the last year the better job the appraiser can do on finding comparables to support the sales price.
We sold a property last year which was a 3BR, 1BA townhome which we advised the Seller would sell better if she added a 2nd bath. There was ample space for the bath by subdividing a laundry/mechanical room on the lower level (next to the 3rd BR).
After marketing for a few months without interest from Buyers as a 3-1, the property sold quite quickly as a 3-2. The added bath cost $4700 (total) - this was a substantial sum for the Seller, but did make the home marketable and appealing to a wider group of Buyers. If the property had lingered on the market, the next price reduction would likely have been in excess of the $4700 spent on the bath.
Please get a CMA from a local Realtor for your pricing. The added bath will make your property more marketable - many Buyers won't even scan MLS data for anything less than 2 baths. This could leave your property out in the cold, regardless of its appeal.
If you want a professional opinion from someone who lives in your area, please feel free to contact me for a pre-sale consultation with no obligation.
Realtor since 1980
(651) 457-HOME (4663)
Take time to do it right and nice. Please, do not do a bathroom just to try to sell high. Do it like you and your family is going to enjoy it.
Typically a house with 2 bathrooms will sell for more money than a house with just one. That's the easy part. The hard part is knowing if the cost of adding a bathroom strictly for the purpose of resale will result in a sales price that will not only cover your expenses but result in a higher sales price. That's hard to quantify without seeing the property and your competition on the market. I think it's safe, however, to say that it would certainly add to the marketability of the house.
To get a more quantifiable answer, I would ask a local Realtor that specializes in your area to do a CMA for you looking at homes that have 2 bathrooms vs. just one bathroom.