Hi Kevin I'm in Herault in LR. It's not easy to make a profit on renovating houses in France imo as you pay quite a lot of notaires fees to buy the property and the market isn't that strong (in my experience people don't move as often as the UK). Obviously it helps if you do the labour yourself to keep costs down but you are then responsible for major works for 10 years should there be any issues. French builders have attestation decennale (10 year guarantee of works) which transfers to the new owner on sale of a property. On sale of a property there are diagnostic tests to be paid for and if electrics have been replaced there should be a certificate of conformity and again the insurance guarantee may still apply.
Agents fees on purchase are high which you'll see below compared to the UK and many people buy direct which is difficult if you don't speak French (so do try to progress this as this could save a lot of money)
We bought our first house through an agent and he deserved his fee as he worked hard sorting out the paperwork with the mortgage company and helped us get planning permission for renovation works (another thing you have to pay for AND if the house is >170m2 you need an architect...VERY expensive compared to UK although there are some English speaking architects around who would be better placed to help.
Other fees on buying: property fees .
There are two types of council taxes foncieres and habitation that have to be paid and these vary greatly depending on which commune you are in. For example Sete in Herault is very expensive whereas some of the smaller villages away from the coast e.g. Margon, Caux, Tourbes are much less expensive.
On selling If there is a mortgage involved then don't forget that when clearing the mortgage there is a fee to remove the hypotheque - ours was 600 euro I recall.
I'd recommend renting a gite or holiday let out of season for a while and deciding where you want to live and if you can and want to make a go of it here. Given the outlay to purchase a property its an expensive event if you decide you can't make a living. We moved here when I was 32, I work from home in IT but my husband has to work in the UK to fund our renovation project...not quite the original plan which was to live mortgage free (we did for a while then started a family and bought a bigger renovation which took on a life of its own). I wouldn't want to leave now, we are well integrated, do lots in the community, I run a local association for kids activities and a parent toddler group and we have lots of friends (both French and English speaking). We've been welcomed by everyone but we did get out into the community as others have said and it makes a huge difference to settling.
Good luck and do try to learn some French before you come - my hubby didn't know any but school French and now he speaks well, understands most conversations although as the kids say he has a terrible french accent...can't do much about that! Good Luck!