From the Studio: A color study is a color blueprint (a plan) by which the Artist works.
Visitors are asked to understand (in the case of color studies) the Artist reserves the right to make changes to the composition for the overall success and integrity of the work. An example of this is seen in Mañana Nos Llega Visita. Note that the right side of the canvas has been extended to introduce a small tree for overall compositional balance. In Madrecita, the poinsettias may be replaced by roses (both flowers have symbolic significance). The exception to halt from making changes - would be the case where a Collector has Reserved or Bought the painting "On the Easel". In most cases Collectors will continue to trust Ms. Hinojosa's suggested changes while the painting remains in progress. These changes are usually for more profound results, thus Celina is often granted Artistic Liberty on what she does best. There are no additional charges for alterations decided upon by the Artist, quite the contrary - the Collector usually gets more than they anticipated.
Final Note: The Detail Windows seen above are still "under construction". What you are viewing are excerpts from the more developed areas of the canvas. Detailing, Voluming, and Varnishing are all part of the final stages of the painting process - and ultimately what bring the paintings to life.