The cost of doing a tenant improvement build out is usually the second most expensive part of your lease after the actual rent. It isn't uncommon for tenant improvement allowances to be equal to six months' or a year's worth of rent -- or more -- and for your out of pocket expenses to be just that high, or higher. However, TIs aren't all created alike, and one dollar in one building can mean something different from another dollar in another building. Here are three strategies to keep in mind: