I’ll reiterate what has already been said, that Europas are very simple. There is a huge amount of information about them online (eg. Here: http://lotus-europa.com/manuals/index.htm), original or reproduced parts are generally easy to find, and there is a wealth of experience and technical expertise on this forum that can make a restoration much easier than it might ordinarily be. Doing a body off restoration seems daunting now but if you have any mechanical aptitude or even curiosity, you should be able to build your own car and drive it. There’s a pride that comes from that that most people will never experience. It’s a matter of motivation, money, and time.
I'll echo Jim's comments, as well as those of other members. There is little that can't be fixed, repaired, or refurbished on these cars. They CAN be a lot of work, a lot of 'fettling', a lot of tweaking on an ongoing basis to keep them going (or getting them going in the first place). It just depends on what your final or intermediate goals are for owning a car like the Europa.
That being said...there is a lot of information, as many have mentioned, about these cars online. The lotus-europa.com above site is one...if you want to read a story about how a car (693R) was renovated, I offer my own humble journal at
http://www.lotuseuropa.us/0693r/journal/index.php as a story about a 9 month turn around from basket case to rolling down the road, and there is certainly a lot of information out there on whether to build, buy, or refinish. There is also the Lotus Europa group on groups.io, which is the latest incantation of the lotuseuropa mailing list that started on onelist back in the late 90s, migrated to yahoogroups until yahoo moved in another direction to end up on groups.io. Lots of great insight there, as well as a searchable knowledgebase at
https://www.prevanders.net/kb2.html which has (i believe) indexed and made searchable every message on the mailing list back to message #1.
So, unlike a lot of special interest hobbies, in the Europa world, you are NOT alone.
In the end, though...all will tell you...these aren't 'investment' grade vehicles. Join the club because you love the car...it won't love you back or finance your retirement...but it will be a fun journey along the way.