Since there are 3 people living in this condo sharing the kitchen, I am not able to pin point exactly who has been doing this even though I have some idea. 

They are known as the Winthrop Factors-The purpose for which the property was initially acquiredThe purpose for which the property was subsequently heldThe extent of improvements made to the propertyThe number and frequency of sales over timeThe extent to which the property has been disposed ofThe nature of the taxpayer’s business, including other activities and assetsThe amount of advertising/promotion, either directly or through a third partyThe listing of the property for sale through a brokerThe purpose of the held property at time of sale; the classification as an investor or dealer is determined on a property-by-property basis.To me intentionally buying a property to renovate it to resell it for profit, twice in the same year, and opened an entity to do it in ....is going to be ordinary income and not capital gains. 

The idea of acquiring a new property every few years to build a strong portfolio is something we’re seriously considering.I appreciate the insight, and it’s great to hear from someone with experience.

When you learn the business after a year or two you can either go out on your own or stay with them. 

I can provide support of checking in on contractors, staging rental properties, walk potential leads to give you an idea of the property in person or what the area is like, meeting with agents, and drafting scope of work for projects. 

First, focus on building a strong network—relationships are key in this business.

It's clear they are not willing to even talk about it and we would have to make a big issue of it - threaten to pull out of the lease or bring in lawyers, and that doesn't seem to make a lot of sense because it will just make our lives hell and cause our business to suffer.

I've got the idea to more positively incentivize my tenants to pay rent by the idea expressed in the following example:- If they pay any later than five days late, they pay base rent ($1,000) + fixed late fee (e.g., $150)- If pay on time without autopay, they pay base rent ($1,000) + "manual payment fee" (e.g., $25 or $50)- If they use autopay for timely payments, they pay just the base rent ($1,000)In the above example, you see that a discount of $25-50 was applied in the case that the tenant chooses to setup autopay to schedule on-time payments via a given PM software.Please let me know if any software comes to mind and also any feedback on the positive incentive idea.Thanks in advance!

In CA, you are legally required to have a CA LLC if you are "conducting business in CA".

Give your state's 'cure' term ("In New Jersey, a tenant has three business days to pay rent and court costs after a judgment of possession is issued to avoid eviction.