Taxes vary from city to city, same goes for ordinance and building codes... Don't know about Denver/Co in general but in MN, any mods done inside your home whether it's a bathroom or kitchen especially if you're going to add or remove something from it's original floor plan. It's recommended that you get a permit from the city. Otherwise, future selling of your property might cause snag.
If you and your husband understands the concept of cutting your grass and maintaining your upkeep no more/no less from your neighbors. You would know that there's a reason behind it, and home improvements are no different; all are subjected to assessments. With the exception, that people don't have to know what your house actually worth with the various upgrades. Just failing to cut your grass or allow weed or undesirables on your property. You can be kicked out of your home if you can not conform to your neighborhoods "standards". When your lot/property is deemed undesirable, it affects other properties around the neighborhood. Some people take offense to that even though they are not in the sell market. Every city/state are in favor of high property values of its residents because they can get more taxes out them. If you're not, the city has no problem with how your neighbors vote you out.