Chessington World of Adventures have quite a few offers on at the mo, so thought it might help to share some of them.
They have a current promo for a ltd time of Entrance Tickets to Theme Park + Zoo + Sea Life Centre for £23pp (less than half price) if booked at least one day in advance. So a family of 4 with kids aged 3+ can visit for £92, kids under 3 go free. If you are a reg carer & accompanying a disabled person, you can also get free entry.
I had a quick look around for some cheap hotels & found that Travelodge had some decent prices, ie Family of 4 staying at Epsom Central (2.3 miles away) in a family room on Sunday 28th August would cost just £42 (flexible rate, cancel for free until noon Sunday) PLUS if you book via Earnaway in link you can get £10 Cashback.
That makes a family of 4 staying 1 night + 4 Tickets to Theme Park + Zoo + Sea Life Centre just £134 + £10 Cashback.(£33.50pp before cashback)
If you wanted an extra day at Chessington then they are offering 2 day Tickets to the Theme Park + Zoo + Seal Life Centre from just £34.60pp so you could visit Sunday 28th, stay overnight & visit Monday 29th for just £200.40 for family of 4 - £50.10pp (obviously if one of the kids is under 3, deduct the cost of their ticket from the overall price)
They also have an offer that is coming up on selected dates in Sept & Oct where there will be a One day entry for 1 adult and 1 child (aged up to and including 5 years) for just £20.60. Ticket available when booked at least two days before your visit date on selected dates in Sept & Oct.
Link goes to the cashback site for travelodge, will pop links to Chessington Offers in 1st post.