Is there a legal limit to the amount of a special assessment per annum?

The condominium I own is located in Colorado. The HOA has recently passed two special assessments to be paid by the homeowners by July of 2014. The first is for a sum of $2,800.00 to be paid by July 2013. The second is for a sum of $10,200.00 to be paid by July 2014. The first assessment is being levied to replace the roofs throughout the complex; a repair which is necessary and well-forecasted by the HOA. The second amount is being assessed in order to replace the siding and upgrade the exterior details of the property with the hope of giving the complex a newer appearance. The second set of upgrades are not necessary but desired by the board and a minority of the residents because of their desire to increase the resale value of their units. My question is: is there any course of action that can be taken to limit the amount of the second assessment in light of the fact that the property is a moderate income community and the amount of the assessment creates a hardship for many?