Since i just received my first HF station today (FT-991A) , this thread is "pure gold".
The layout of my Summerhouse & lot , will probably force me to use an EndFeed for the HF part.
I expect a EHFW at around 23m long ... I'd love to run 80/40/20/10 , i don't have room (space) for 160m.
If i'm luky i can get it 15..20 feet up in the feed end , and maybe 12..15 feet in the other.
Well, an EFHW, as the name says, needs to be 1/2 wave on the lowest frequency, so for the 40m band you'll need 20m of wire; now, you wrote you don't have enough room, in such a case, and also since the 991 has an internal ATU, did you consider a so-called "random wire" antenna instead of an EFHW ? Let me try an example; let's start from the wire lengths shown
here (the green numbers down the page) and let's say we pick the 84' length (while a straight line is preferred, the wire could also be laid out with some [wide] angles both vertical and horizontal), such a size will allow to cover all bands from 80 to 10 meters, and while the antenna won't be so efficient on 80m being around 1/4 wave on that band, it will still work; such an antenna will require a counterpoise system, in this case a 17' (at least) run of insulated wire dropping down from the feedpoint will suffice (a section of wire may also lay down on ground if needed); add a
9:1 UnUn (you may use an FT240-43 in place of the FT140-43 if you want) followed by a
choke, connect your coax and you'll have your multiband antenna; sure it won't be a "beam" but for a starter it will serve you honestly, then, as for all things, there's always room for improvements
my 2 cents
[edit]
For further informations and additional possible lengths for the "random" antenna, see here too
https://udel.edu/~mm/ham/randomWire/HTH