Decorating a house from scratch

[Glasspen]

I know this sounds like fun but I am really feeling quite overwhelmed with knowing where to start.

It's a second home near family, budget probably mid-range. Someone suggested getting an interior designer to plan the space and then choose the furniture from that - anyone else done something similar?

If you really can't visualise the rooms then yes and interior designer may be able to guide you. Be very up front about your budget. Hopefully, the cost of the designer will be offset by the deals they may be able to get through their contacts and savvy buying.
Or if you have a friend whose style you admire, maybe they can help? But it's a big job so don't take advantage (which is why it's a profession too).