HELOCS do exist for rental properties but you are usually capped at 65-70ltv and these will most likely require a full underwrite that takes into consideration taxes, income, dti and all the normal quasi-associated red tape.

And will the lenders take into the consideration the money that I'm earning now and from my business?

It will be triggered upon sale OR refinance, so if you think you might want to refinance in the next couple of years (or at least have the option), you may want to consider a shorter penalty length. 

Should I pull the trigger or just clean up the  unit as is.

Supply: The availability of MFH is considerably lower compared to SFH, which can pose a significant challenge when searching for the "perfect" property, especially when personal needs come into play.

Cost is always a consideration, but since this isn't a pure investment, not looking at it as cash return, cost, value of improvements, etc. 

For example, if you raised rent by $25 a month that is not likely to trigger them moving but it does help control the gap that could develop between your rent and market rates.Each year you skip widens the gap and makes it harder to close and more likely to trigger a move. $400 is tough to recover in one change without triggering a move.I have learned the hard way that I really should not skip rent increases every year, even if they are small.

Regardless of lack of "significant" consideration.  

@Ly MaCurious if you ever pulled the trigger.

These can often lead to meaningful connections that turn into investment partnerships.Legal and Ethical Considerations: Make sure any partnership agreement is vetted by a legal professional to protect all parties involved.