In astrology, there are several ways of dividing the chart and determining topics and prevalence of themes in a person’s life. One of the most fundamental expressions of this is by house system. Unfortunately, the question of what house system is most accurate or most historic has become a bit of a holy war. It’s a way of recognizing who is aligned with what group of astrologers. I have friends and teachers on both sides of this divide, those friends have proven themselves competent on numerous occasions despite their difference in approach. The short answer is, as a client, it really shouldn’t matter to you which house system I use as long as the consultation proves accurate and useful. If you would like the longer and much more technical answer, read on.
My own style leans toward the early medieval more than late renaissance these days. But that was always my trajectory and ambition. I haven’t yet fully integrated everything. For now, when investigating a birth chart, I use a mixture of the Whole Sign and Alchabitius house systems. That approach is credited to Zoller, but I apply it a bit differently, as taught by Benjamin Dykes. I am also glad I studied Hellenistic Astrology with Chris Brennan because my advanced understanding of profections really helps with predictive natal timing. For question and event charts I still use the Regiomontanus Houses, the same used by the famous 17th century English astrologer William Lilly, as taught by my mentor Christopher Warnock. For making astrological elections, I'm also early modern with my use of Regiomontanus, but that's because I'm currently studying a very specific text. I am not currently making talismans, but if I were, I would likely use Alchabitius or Porphyry, those are the systems that would have been most well known to the writers of the texts that would become part of the Picatrix (paid link), and I believe that those are the house systems that best express my own theory of astrology, which is especially important in magic.
What is my final form? I have no idea. At this point, I suspect I'll end up leaning on the medieval works and eventually hammering out all my astrology to use something akin to my approach to natal with Alchabitius and Whole Sign; focusing more on Alchabitius when the astrology is more immediate (questions, events, some elections), balancing between both house systems for mid-term such as birth charts, business charts, some event charts, and leaning more on whole sign and fixed stars for things like mundane, that is the rise and fall of governments and religions, but I can also see a world where I flip back to late renaissance and bring all that I've learned with me to practice more in the vein of Lilly. I'm currently undergoing another round of questions study that uses William Lilly’s Christian Astrology (paid link), so we'll see where this circumambulation leads.
All that said, I do have a set of rules that I apply to myself that have served me well and might be helpful for anyone looking for a bit of guidance to studying different astrological house systems and techniques:
1) I practice using the technique exactly as it was taught me until I have a feel for what things are supposed to do and understand the practical application. Once I've done that, I give myself permission to consider my personal philosophy and theory of astrology. This is where getting a handle on worldview comes in helpful, and why I am greatly indebted to my mentor Christopher Warnock for having me read The Elizabethan World Picture (paid link) before starting my astrological studies. It helped me understand the mindset of William Lilly, William Ramesey, and John Gadbury, who wrote the texts that provided the foundation of my own understanding. Now each time I start playing with other techniques or eras of astrology, I ask myself about the assumptions that are made with the technique. I force myself to be brutally honest about how my assumptions may differ from theirs. Like any artist, you can't break the rules until you understand them.
2) I don't change systems to get a desired result. If I set off to read a question chart, I won’t' shift house systems because it tells me what I want it to. Likewise, election or birth chart. If you change the rules because you’re not getting the results you want, it's not really insight at that point. It's a bit like starting a tarot reading, not liking the result, and going for another deck then starting the whole process over again. I'm a big fan of finding unique ways to break the rules - but to me, once a game is in play - you don't change the rules. I have my own metaphysical reasons for this, but it boils down to lying. My own view is that there is an underlying Logos in play, but your own perception of Logos differs based on your perspective, the classic blind men and the elephant analogy. In the theological doctrine of inspiration, the idea is that the would-be prophet is molded into the correct instrument of divine revelation through his or her trials, personal connections, victories, and defeats; the whole life up until the writing is inspired. This differs from the popular view that there is a cell phone that connects you with God and He dictates exactly what is to be written, if only it were that easy. My view is that astrological interpretation is an inspired event. In my case, I have learned that means I can't cheat my way out of it. Others may not be under that constraint.
3) I recognize we all assemble our respective toolkits. Sometimes we get lucky and have great teachers who give us our first kit. But, at the risk of coming across as far too nerdy I’m going to use a Star Wars analogy. In the Star Wars books, when a Jedi graduated from training, they had to build their own lightsaber using a special crystal called a kyber crystal. We all must eventually head out and seek out our own kyber crystals with which to build our lightsabers. Just because my lightsaber is green doesn't mean someone can't use a blue one to equal effect. If I am seeking a consultation from someone, it's not my place to question their tools, and I encourage that behavior in my own clients. Most of the time, I don't even explain the astrology to them unless they ask for it directly. I care about prediction and results. If someone is blessed to be able to generate accurate prediction by using only the skill-up constellations in Skyrim, more power to them. Personally, I want to be the kind of Astrologer that roamed the streets of 10th century Baghdad, 13th century Toledo, or 17th century London. For me, my study as much about plugging into the tradition as it is about getting things right. I want to add my own small voice to those of the great giants that have come before me. But, if I am in need of an astrologer as a client, I will not hold them to my school or standard of study, just my standard of excellence.