In the DFW area, many cities have online permit systems and have the subs listed. For example, I can see which pool builders were used for each pool in my neighborhood and what subs they used for electrical, plumbing, etc. Going that route, the main savings is essentially paying a pool builder a Master Contractor and Project Management fee. I investigated going this route (as I was building my second pool), priced it out, and decided the Pool Builder "surcharge" was worth it.
Respectable Builders have strong relationships with their subs as it is built on hundreds/thousands of past and future pools. Many builders get a lower rate for subs than what an individual would. They also have a level of influence with them when it comes to resource scheduling and quality of work. The result of this is a sub may be willing to "re-work" an item unacceptable to the Builder but not for you (as their relationship with you is one job, limited $$s). I'm not saying this would be the case, just that some subs are better than others and it is a risk to consider.
After I priced it out, I was going to save about $7K going the DIY using subs route. Not an insignificant sum, but I also estimated it would take 4-6 months for me to complete due to limitations in my schedule to oversee the work and scheduling with the subs (ex. my builder may be able to get a guy out the next day, but if I scheduled it ....it would be 2-3 weeks out). So for ~$7K extra, the builder I chose provided the Project Management, accountability, warranty, and went from dig to water in less than 40 days (and if a sub screws up, someone other than me has to eat the cost). BTW, to save more money, I determined I would have needed to use different subs from the majority of area Pool builders or do some of the work myself. Going that route saves substantially more, but also would have increased my build time. Note: I did contract my deck separately from my pool builder and saved considerably there.
I'm not discouraging you, but providing feedback to consider. Also, Houston area, being a different market, may have cost differences that play to or against the DIY route.