This probably isn't a direct answer to what you are seeking to know, but a few general basic things to think about before you make the decision.
1: Other homes foreclosing "usually" has no impact on your homes value.
2: Do you plan to stay in your home long term (10 years plus)?
3: Did you buy your home at below fair market cost, where investing 30K would not turn you upside on the homes value?
4: Did you get more then 1 estimate to perform the work?
Things I would base my decision on;
1: How badly do I need the space?
2: Can I afford at the present time to finish or add additional space?
3: Know that making this investment may or may not increase the value of my home.
4: Am I okay with knowing that investing 30k in my home, that I may not recover this money when I plan to sell the home?
5: Get at least 3 estimates.
6: Research each contractor thoroughly.
7: Read the fine print.
8: Make sure you know all the possibilities in advance for extra expenses or cost of problems or issues that may occur in advance.
9: Can I perform some of the work myself and save a few dollars without risking the quality of work performed?
10: Discuss all options with my better half and make sure you are both in agreement on EVERYTHING.
A decision if you should do it or not do it, is all a personal decision on many different factors. The estimate of 30K may sound like a lot to some and then sound like a little to others. Keep in mind adding a bathroom to a house just being built usually has the cost of 5k-25k depending on fixtures, plumbing, tile, etc... Roof work to add skylights can range anywhere from 1k-12k depending on how much roofing work and cutting has to be involved, the pitch of roof, etc... Then keep in mind, walls that need to be put up to separate the different rooms the bathroom, closets, etc... Floors that need to be finished tiled, carpet, hardwood. etc... Electrical that has to be installed for lighting, switches, outlets, etc... Ceiling work that may have to be done to give it a finished look. Any trim work that you would want done. Don't forget any permits, and inspections that must be purchased to perform all work involved and make sure everything is performed by building code and pass all safety codes (make sure you save all inspections showing passed building codes and safety codes, you will more then likely need them if you ever sell your home). This isn't a fool proof list of all that is involved but a general idea of all the different types of work involved. One other thing to keep in mind is that since this is an attic, their is the possibility of walls and ceilings and floors on lower floors that may need to be repaired and or replaced in performing this project.
Another thing to keep in mind is a small room of 700 square feet or less will cost more per square foot to finish. The bathroom is the most expensive room to finish per square foot, and the cost must be spread over the entire square footage cost. So the smaller the room the higher the square foot cost.
Good Luck
May all your dreams and wishes become a reality!
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