If this is their first flip and you already have some experience then it could turn into a win-win for both of you. 

It seems like a good option that is win win.

Please note evictions for violation of the lease are difficult to win.

That way, everyone wins.  

I believe its easier to lose short term versus long term, long term allows you to pay down the principle and hopefully expect some appreciation, i think the final goal should be to have properties free and clear some day, if you buy right and hold the property, manage it well, i see it hard to lose money over a 10+ year term doing the buy and hold scenario, on the other hand you can easily lose money buying and selling several homes yearly.  

Looking to begin very lucrative win-win relationship!

So, in Texas that would be a big win.  

If your reason to change the zoning is compelling enough, a win win for you, the city and the neighborhood, then you could make a proposal to the city that they do it for free or give you some sort of tax credit which equals the amount or greater.Look into it.

I would think 150k would easily cover the cost of reno to include new wire and plumbing although I seriously doubt electric and plumbing are shot in all 4 units

Offer a win-win situation like that.