http://www.policylibrary.tax.Virginia.gov/OTP/policy.nsf/0/755137127828f18d852569f2006b58c1?OpenDocument is the link to the:
Virginia Tax Administrative Code
Code Section: 23VAC10-210-410
Tax Type: Retail Sales and Use Tax
Brief Description: Contractors respecting real estate
(Expert - this seems to cover the installation of tangible property
that you purchase, and if you bill separately for installation):
Items G. and H. seem to cover your question, depending on how you invoice installation. Again, from the VA Code cited above:
G. Contractor or retailer selling and installing tangible personal
property that becomes real property after installation (including fences, venetian blinds, window shades, awnings, storm windows and doors, floor coverings, cabinets, kitchen equipment, window air conditioning units, and other like or comparable items).
A person selling and installing tangible personal property that becomes real property after installation is generally considered a contractor, except that a retailer selling and installing fences, venetian blinds, window shades, awnings, storm windows and doors, floor coverings (as distinguished from floors themselves), cabinets, kitchen equipment, window air conditioning units or other like or comparable items is not classified as a using or consuming contractor with respect to them.
For purposes of this subsection only, a "retailer" shall be deemed to be any person who maintains a retail or wholesale place of business, an inventory of the aforementioned items and/or materials which enter into or become a component part of the aforementioned items, and who performs installation as part of or incidental to the sale of the aforementioned items. As so defined, a retailer is not classified as a using or consuming contractor with respect to installations of the aforementioned items. A retailer must treat such transactions
as taxable sales except that installation charges when separately stated on an invoice are exempt from tax.
Persons who are not classified as retailers within the definition set forth above and who sell and install fences, venetian blinds, etc., are deemed to be contractors and must pay the sales tax on such items at the time of purchase.
"Floor coverings" (as distinguished from the floors themselves) include rugs, mats, padding, wall-to-wall carpets when installed by the tack strip or stretch-in methods, and other floor coverings which are not glued, cemented, or otherwise permanently attached to the floor below. Persons selling and installing floor coverings which become permanently attached to floors are deemed to be using or consuming contractors with respect to such items. Such floor coverings include carpet, wood block, cork, tile, linoleum, and vinyl floor coverings when glued, cemented or otherwise permanently attached to floors or plywood and concrete subflooring.
Both retailers and contractors are deemed to be the users or consumers of supplies used in installing tangible personal property that becomes real property after installation. Therefore, retailers and contractors are subject to the tax on their purchases of tacks, stripping, glue, cement, and other supplies purchased.
Subsection B is applicable to persons engaged as contractors with respect to the installation of fences, venetian blinds, etc., and also as sellers of such items at retail to customers, including contractors, on an uninstalled basis for use or consumption
H. Retailer selling and installing tangible personal property. Any person who sells tangible personal property at retail and installs such property as part of or incidental to the sale is a retailer and is required to add the sales tax to the sales price. The tax does not apply to installation charges when separately stated on a sales invoice. If the installation charge is not separately stated, the tax must be computed on the total charge.
Retailers are deemed to be the users or consumers of all supplies used in installing tangible personal property. Therefore, retailers are subject to the tax on all such supplies purchased.
It does not appear there is a separate exemption for disabled customers.
Thanks again from Just Answer.