Ton of super old housing stock with a lot of Heroin / Fentanyl. 

This article will help provide some insight into that question.First, it is crucial to understand that the real estate market and the stock market are two different markets.

Bonus points on the fact they keep it in stock in store.  

It offers a secure and transparent process for both buyers and sellers.NoteTrader Exchange: An online marketplace where you can list your note for potential buyers.LoanMLS: A marketplace for buying and selling mortgage loans and notes.FCI Exchange: Another platform where you can list and sell your notes to investors.Note Investing Forums and CommunitiesBiggerPockets: A popular real estate investing community where you can network with potential note buyers.LinkedIn Groups: Join groups focused on note investing and real estate to connect with potential buyers.National Note Group: An online community where you can connect with other note investors.Note Brokers and BuyersNote Brokers: Engage with reputable note brokers who have access to a network of note buyers.Local Real Estate Investor Groups: Attend meetings and network with local investors who might be interested in purchasing your note.Financial InstitutionsCredit Unions and Community Banks: These institutions may be interested in purchasing performing notes.Private Equity Firms: Some firms specialize in acquiring performing mortgage notes.I hope this give some direction regarding your situation.

We have a GroupMe in DFW that we exchange ideas and it is an easy way to get direct support from other investors in the area.How to choose the write strategy, you have to educate yourself and create a good team around you that you can trust.Feel free to DM me for access to the groupme.

Is there a full-sized gym nearby that would be willing to waive their start-up fees for your residents in exchange for a referral from you?  

Sell the house and invest in stocks.

I agreed to take out an under ground storage tank in exchange for a lower price.

Looking forward to seeing you around and exchanging ideas!

Knowing this information, should I sell and take 300k(ish) to a bigger multifamily or apartment via 1031 exchange?