Past sand and topsoil you may find the little fella wanting if you get into fill dirt. I don't know how deep you'll need to dig in texas, so just a consideration.
Typical is 18”-24” to run pool pipes here.
Look into a Dingo TX1000. They come in a wide track(won't fit a 3' gate) and a narrow track as well. You can get one brand new for something like $42K. You can get a good trencher attachment for it for somewhere around $3k. Believe it or not, but they also have a small hoe attachment for it. I have no idea how much it is, but I have seen it work, and it works well as long as you aren't tugging on huge rock or roots.
Kubota makes an equivalent. I think it is the SCL100 or something like that, but they are more prone to tip on a slight grade.
Dingos are like Swiss army knives for small equipment. Also, much smaller and lighter to transport on trailer. You don't need a monster truck or a CDL/ Class whatever license due to DOT overweight issues.
I have Dingos and a Kubota. AMA.