New home owner - Property line concerns

[Kristen Davis]

Hi, there. I am a new home owner in an up and coming neighborhood near Denver, CO where there is a lot of gentrification occurring. I hope to one day rent my basement, so that I can pay off my house quickly and maybe start to invest in other properties. My intention is to learn more on this website. My house was a fixer-upper and I cannot afford to hire a real estate attorney or pay for a property line assessment. An investor owns the property right next to my house and their property line markers are two feet into my existing property. It appears that they have also removed the property marker pin that was in the sidewalk (I can see where they dug it out). If they intend to take over that property, I would have to tear out my brand-new fence, landscaping and concrete. I have tried to get help from the city/county, but they have not been helpful. I am not sure what my rights are and what the standard protocol is IF in fact their property assessment is accurate. Apparently this investor did not pull a permit when they did the demo (they left asbestosis material and trash in the entire yard and only removed the siding on the house). A neighbor called the city and the investor was fined and was told to remove the remains. Now there is a giant hole where the house was with no fencing. I have a plat map, but it is very tiny and therefore difficult to decipher. I am hoping to get some friendly and free advice/information regarding the following topics:

- What should I be aware of in this situation?

- Can they just start tearing down my fence and encroach, given their property line markers?

- What are my rights in this situation?

- Is there anything that I can do aside from paying for my own property line assessment and/or hiring an attorney?

- How can I get a copy of the rules and regulations for sidelines, setbacks and easements and height (if there are any)?

- How can I find out, if possible, if they completed a survey for the building permit?

-Is there a way for me to find out who the owner of record is, what company is going to be doing the new build (if that's what they intend on doing)?

- I've been told by other neighbors that they intend to build a duplex, but that they don't have enough property to do so legally, so I am wondering if they are trying to push into my property so that they have enough land for a duplex. Not sure if it is possible for any corrupted practices regarding property line surveys or if it is highly regulated. 

Thanks in advance to anyone who is kind enough to provide any information. 

Kristen