In our climate here I would hope that you have at least a usable heating and air arrangement? If you look at the various listing services (MLS< etc.) they all list the method of heating and cooling in one form or another. As a result you might face a roadblock to selling with window air/heat/baseboard heat/etc. if your home is priced the same as others with central heating/cooling.
As just a general rule of thumb it is going to cost approximately $1500/ton just to install the exterior condenser and interior air handler/evaporative cooling unit. One ton of heating and cooling per 500 Sq. Ft. of home. Then you will have the costs of duct work and grills to consider which is expensive as well, even though the materials are relatively inexpensive.
In my opinion I would look at all aspects of your home, and not just this issue, to make that decision. I would expect that your home is an older one if it does not have central heating/cooling already. What else would need to be done to compete with other homes for sale near you? Would you need to update plumbing, add more insulation, replace the roof covering, upgrade this or that, repair this and that? After you have done all of those things how much would you have spent? Is it more than the return from selling it?
Price all of the work out but before you actually do all of that work and then speak with a few RE Agents and and have them give you an idea of market value compared to other comparable homes recently sold, or currently for sale, in your area. They have the ability to tell you what other homes old for. Then make a decision whether you want to perform all, some or none of the work and just price the home accordingly to draw interest and a sale.
There are times when it is just not worth the aggravation to find good contractors to perform the work properly just to take a chance it will help sell the home.
If you are not sure what might need to be done you can always call a Real Estate Inspector to perform a thorough inspection of your home. A good Inspector will go through your home and document everything! It will also help you see things you might not have thought of and could potentially cause you money during the sale when the buyer has the home inspected.
Emmanuel J. Scanlan
PS Inspection & Property Services LLC http://www.psinspection.com
TREC License # 7593
International Code Council, Residential Combination Inspector #5247015-R5 (Electrical, Mechanical, Plumbing and Building)
Certified Infrared Thermographer (ASNT-TC1A Standards)
Texas Residential Construction Commission, Third Party Warranty Inspector #1593
Texas Residential Construction Commission, Inspector, County Inspection Program
Texas Department Of Insurance, VIP Inspector # 08507061016
Hayman Residential Engineering Services, Field Technician
CMC Energy - Certified Energy Auditor
Knowledge is power, but sharing knowledge brings peace!!
Bruce is correct however there is a benefit work with an agent comp true value of your home, determine your best interest. Home improvements money vested can over value a home for a given area.
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Realty One Group