Lastly it may be a long wait for someone to bring in a home just to rent the property from you.In order to have real estate investments that are 'life style altering' you need more capital. 

A process that doesn’t involve any PDFs that could potentially be altered?

Bathroom removal and a cooler install likely involved plumbing and electrical work, so your main concerns are permits, code compliance and liability since unapproved alterations ultimately fall back on you as the owner.

They won't be able to alter their forms in this way. 

Then make necessary alterations for better sound control before re-renting.

The problem we see a lot where I work is fake/altered permits, stolen stickers/hangtags, abuse of visitor spaces, and the most common no parking permit! 

You need to find out what the project requirements are for performing renovations...they could have rules that will slow your roll, including regarding plumbing or electrical alterations.

I allow them to paint or alter things in their houses.

No alterations.  

TIA   :)First you want to follow Dodd-Frank, then make the lease date and the option date the same date and length of time, qualify the same way you would as a lender, get as much of an option fee up front as you can, don't give access until they have paperwork and fees have been collected, decide if you will allow alterations and write your option agreement accordingly, know what the law allows, use a contract for your lease and a separate contract for your option agreement, use an attorney for your contracts or use contracts previously written by an attorney, treat them like they are buying the house, set your future sales price in the option agreement.