I like the adding $25 to their rent until they pay you back, but they could protest this since your lease doesn't address it specifically.

We went and protested property value and they lowered it from $103k to $90k but taxes went up 14%,Ugh seems like cant win,house isn't even worth the $90 compared to neighbors houses.

Long answer for this question...Short notes:1. research2. legwork3. sourcing materials/vendors4. insurance audits on their properties5. tax protests yearly on their properties6. deal sourcing/partnering+ much more.

Once you've purchased the property, make sure to take any Exemptions you can, and make sure to protest your tax valuation every year. 

Unless you think that the supermarkets where we buy our food don't do things like put wheat products on their shelves that include sawdust fillers, the gas stations never doctor their pumps to register a full gallon every .97 gallons, the waiters have never spit in anyone's food, the pharmacies are always giving you your medicines at a fair price, the public school teachers who care for our children are all passionate professionals instead of CYA pension-seekers, and of course that we have statesmen in political office with clean hands and clear hearts and pure thoughts running through their heads every moment of the day...All the hysterical protestations and declarations of extraordinary personal integrity here seem a bit overdone here, don't they?

Collin County is very inflexible when it comes to protesting the tax appraised value. 

Who needs a good, fair landlord who charges reasonable rents and keeps things working.If I could just get off these 80 hour workweeks at the day job I'd be in Olympia protesting.

Demand has still generally outpaced supply here.As for your tax strategy, being out of state puts you at a disadvantage for homestead exemption AND the likelihood that you would protest your taxes is low.. being that it's time consuming for you to be present for the hearing.  

I think it was a huge mistake for the protesters.

to sell their turnkey property.Here in Texas you can protest your tax value annually as a regular process during a set window, and you can also protest if you buy a property outside of that window if your purchase price was well below the value on the tax rolls.