How exciting you are considering homeschooling!

HOD offers outstanding curriculum that is pretty easy on us moms.

There is basically no prep. I agree with the pp about LHFHG and Bigger Hearts. Unless your ds is a fairly strong reader, does well with writing quite a bit each day, has had grammar basics already, preferably has had cursive, is pretty independent and good at following sequential directions, and finally is somewhat familiar with Charlotte Mason skills of oral narration, dictation, and copywork - BHFHG would be the better starting place rather than PHFHG.
BHFHG teaches some pretty foundational skills.

We are doing it right now, and having been down this road before (my oldest is now in RTR), I can see how crucial BHFHG is for helping him to "launch" into the rest of the guides. BHFHG will have you teaching more than PHFHG. However, I'd always, always, always rather teach what I'm intended to teach in an HOD guide, rather than teaching what was intended to be done independently in a guide (as PHFHG could be). This is because if I am teaching something that was supposed to be independent, as that skill progresses each year in each guide, I may be teaching it forever, whereas if I had just properly placed my ds, he could have taken it over beautifully after I'd taught it the first time when it first came up in an earlier HOD guide. Not to mention there will probably be an adjustment period as your dc transition from ps to homeschooling.

However, if you look at the placement chart and your ds places squarely in PHFHG, he will probably do fine, as long as he is mature in independent skills as well. We've found the placement chart to be extremely accurate. I think you will love HOD! It is such a wonderful way to homeschool. We are happyily homeschoolling because of HOD!
In Christ,
Julie