The law states,"the time of such notice shall be sufficient if it is equal to the interval between the days of payment or thirty days, whichever is longer" so just as an example, if a notice to quit is served on May 15 to tenants who are required to pay on the 1st of each month then landlord would not be entitled to a judicial remedy (i.e. going to court) until at least July 1 because July 1 would be the first instance where the tenant’s rent would be due after their tenancy at will expired. 

This could be complicated being that there is only 1 legal unit and FHA guidelines require the purchaser to live on the property. 

Its one event after the other, and although I'm extremely grateful for the experience I am gaining managing my own property, and dealing with such a complicated tenant, I don't know what my legal options are since we cannot evict anyone until October 2021 or if i even have grounds for eviction (New Jersey).I'm 29, and The tenant likes to push boundaries to see what they can get away with. they confuse my age with lack of knowledge and seem to take advantage of the situation.

Adds a lot of complications, like if something breaks, or doing the roof, and it might limit who buys your place in the future.

After looking at Appfolio and couple of other softwares to manage my properties, I came to the conclusion that they're too over complicated for my needs.

The more complicated answer is if you do quitclaim the property you will be in breach of the mortgage agreement in the bank May exercise the due on sale clause.The third scenario would be to buy commercial property using commercial lending any such instance buying and financing for an entity is quite common practice.So, coming back to the beginning of this answer it's all about the type of investment you're looking to do and the risk involved in doing so.I do want to share my two cents on the matter. 

Without running the math, I'd be hesitant to add complication to a property.

Why add more stress or make your life more complicated by working to resolve the current property owner's issues on a this project?

Due to many complications, we fell into default with the 2nd lien holder and owe 170k and are facing foreclosure, set to be sold in auction soon.

While an LSA can play the role of collecting / remitting payments, accounting and enforcement in the event of default (foreclosure), its not necessary to have an LSA and may add extra layers of complication or expense.I’ve found that if you have a reliable escrow agent: they will handle the crafting of the note and mortgage, arrange for necessary signing / notarizing / recording of the documents & handle distribution of loan funds.