I did this - it wasn’t ‘cheap’ because we paid for all booze and a sit down meal with caterers but having a buffet and a paid bar wouldn’t knocked £4K off I reckon.
I used a wholesale flower company and did my own table arrangements and bouquets.
I made my own invitations
I bought the booze wholesale from Majestic and in bulk from Tesco
I used an iPod with a carefully arranged playlist that lasted the whole night
I used a church hall which was £500 for hire from the Friday afternoon before to midnight
My friend made my cake
I made my table plan, place cards, table numbers etc
I made edible favours which were very popular and everyone ate them within seconds of sitting down
My wedding cost £11k for 80 ish people and a rough breakdown:
£4K catering
£2k booze
£1k dress
£500 reception hire
£400 register office
£1k rings (two simple platinum bands)
£400 all flowers
£100 ish - stationery
£200 - glass/tablecloth hire
£150 chair covers
£250 decorations (helium balloons, table confetti, favours etc)
£100 a lot of donuts for evening buffet
Worth mentioning that my PIL paid for our car - my friend was going to drive me in her Corsa as I don’t care about that stuff but they insisted on a fancy car for us.
We were also given £5K as a gift from family. Our original budget was £6k as that was what we felt we could afford and would have had a lovely wedding with that too.