Hi Sinead
Everyones situation is different but for what its worth here is what we did. We purchased in the SoF last year. Initially we had a similar idea, but smaller budget, to you. As in family property, rent part-time, self-use and possible retirement use.
At the time I spoke to a knowledgeable colleague (tax consultant) about the tax implications etc. However, IMO the most valuable bit of advice that she gave was not to mix emotion with investment.
In other words what she said was if you want a holiday/retirement home then buy that but dont expect it to yield a substantial (esp after costs of renting etc) or regular income. Simply view it as our home in France that perhaps make some contribution to its own cost.
Or buy an investment property with zero emotional attachment that you simply rent out and forget about it.
We went with the zero emotional attachment and for us that was the way to go.
Personally, if I had a budget of 500k (and I mean a borrowing budget not cash) I would look at the possibility of buying two properties. One as a pure investment property (appartment for less than 200k) the other as my personal use property. Especially if you can only use the villa for only a couple of weeks in the year. Although you would have to settle for a smaller villa. Spread the risk. Then come retirement you have two properties in your portfolio to use towards you ideal retierment villa.
Although, like you I would be interested in hearing from people who have managed (or tried) to combine personal use/investment in the one property.
Perhaps the reason you have being toying with this decision for a few years is that you are mixing emotion and investment. Would it be easier to make the decsion if it was a pure investment?
Cheers and good luck.
CrazyWater