Woosh are a good place to purchase, excellent customer service (but not a local bike shop). They have a folder quite a bit under £1000, http://wooshbikes.co.uk/?gallego
Quite a low power battery is one disadvantage of that particular model (but a lot of folders have even less); won't matter for relatively local riding most people will want on a folder. I haven't seen/used that particular bike, but Woosh are an honest company that won't try to sell you an unsuitable bike just to get a sal; ask their advice.
You probably need to post a bit more about how you expect to use the bike, what you are like and what your local terrain is like to get the best answers. Also try asking on https://www.pedelecs.co.uk/forum/forums ... -i-buy.40/
, that's a lot more active than here with more people really into e-bikes (even if some do go over the top sometimes ...).