Commuting from Farnham Common - parking at Gerrards Cross/Slough?

[PoppySeedBun]

We are currently looking at a house in Farnham Common, Bucks, and considering the move out of London (well, Brentford :))
I work in London, currently 3 days a week, so would need to commute.
It would probably mean driving to station to get the train, but I just have no feel for how doable that would be
Any advice on traffic/parking around Gerrards Cross/Beaconsfield in the mornings? My current plan is to try and find a nursery close by for DD, then drive to Gerrards Cross (hopefully) park, and train into Marylebone.
What am I missing? Anything (beyond horrendous cost of car parking/season ticket) that I need to consider before we make an offer?

What time of morning? I've worked in those areas for 20 years (not done it now for 5 yrs so things may have changed) and trying to get into B'field train station from both the Amersham side (A355) and via the old town are hideous. To do a mile in a car I would have to allow 30 mins if it was between 7.45 & 8.45 am. The station since having had an extension is better for actually finding a space now! Pretty much all roads within walking distance are double yellow lined.

GX was ok to access but the car park is small compared to the number of commuters. (Don't know if it's been extended recently) and again, you won't be able to park on the road if you want to be within walking distance.

Thanks. I'm guessing it would have to be after 8am as I'll need to drop DD at nursery before I go. I could perhaps flex start time with work to go later, but I'm guessing that would make it harder to park.
GX looks like it has a fair bit of parking, but don't know what's it's like in proportion to the number of users...