On average, listings lease in the $10's per square foot per year. The Doña Ana County submarket is going through a a rise in rates. In the last 3 months, the median rate rose $18 per sqft per year.
In the last 90 days, 29 listings have been made available, which means listings most likley are going fast. You'll want to be prepared to make an offer immediately. About 166% of the listings in the Doña Ana County are subleases, so you might be able to sign a shorter term by taking over a previous lease. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,000 sqft. Most properties in this area are close to 1 stories. Most buildings in this area were built in 1959 and are Class B.