What options does your lease give you?

Also, within this approach, the option that attracts me the most is purchasing and installing a 'tiny home' on a campground that allows it.

Off-market deals are key if you go this route, so networking is huge.Out-of-state investing is another option people love, especially in markets like PA (Philly, Scranton) or even down south where prices are lower, and the landlord-tenant laws are more forgiving.

For example, I will send a tenant the lease renewal options and give them one week to respond.

Quote from @Samuel Pavlovcik: @Nicolas Tow Your Architect is correct that it sounds like the only option for you would be to obtain a Zoning Map Amendment to change to RT3.5 or higher.

. - Any interest in getting on a conference call and discussing our options, given that we are in the same boat? 

I think a better option is to get a job in property management.

Many opt for other investing methods in their SDIRA like private lending, crypto, private equity...anything except collectibles and life insurance.Note that a Solo 401k is exempt from UBIT on leveraged real estate so if you have self employment activity and no full time employees save for you and your spouse you should consider the Solo K as an option. 

In other words, an IRR calculation.Have you ever considered doing lease options?

There is an incredible amount of points to consider when weighing the options on something like this and honestly, I don't recommend it to very many people at all ....even seasoned tradesmen and investors.