Should I build or should I buy elsewhere?

[Robert Solis]

Question for the forum. I currently have a two story home. We live upstairs and have a bottom room with full bathroom and kitchen that I rent out with a private entrance-all permitted. There is downstairs office and enough space downstairs to add a bathroom and a  private entrance door or they can use the garage door, private door preferred. Preferably this would be for student as they don't need to cook and usually eat at school.  I have about $20k, but the cost to add this type of room (bathroom, private door) is about $40k, exceeding and double the costs - ouch. Many contractors are quoting 2x, citing covid and surge in construction projects - supply-demand. With a bathroom/stand up shower, I can confidently secure a $1000 month cash flow as we have a few colleges in the area and next to a bus top which takes them to college- that's nice.   Would you build the bathroom/private door, maybe getting a construction loan, or go out and invest this $20k in a property elsewhere? FYI, we are familiar with our area and not really experienced outside of our area. Not against going outside to invest and that's the bigger plan. We've already refinanced the home in 2021, not sure we can refinance again, maybe a construction loan?  Any thoughts, Thanks Bigger Pockets community.