We long line off the back of the boat occasionally, and also drop it for an hr or so soak.
Good to find out where fish are (or are not) when hard fishing  espec over winter.
To buy a reasonable line line can cost a bit.. if buying dont buy cheap.. mainly because of the handling set up.
Here is a basic tight budget setup.
Buy a reel of 3 or 3.5mm braid from a haberdashery shop.. yep same stuff....approx $45 and u will only use less than 1/2.
Reel.. and electric extension lead reel.. about $20 from megta mita
Couple buoys....$12 each .. or 1 ( LEGALLY Requires name and phone number on them)
20/ 25m is more than enough for the drop between buoy and sinker.....about 300mm briad off the bouy to a loop on the end of the main line
Sinker(s)...an old big crescent or tractor pin... again attached same as buoy
Tie a loop.. surgeons knot about 2.5 m from the sinker knot... u may have this distance to suit how fast or slow u can clip the hooks on at your convenience.
Hooks use the Nasan long line hooks or owner 4 suicide hooks (MAX LEGAL NUMBER 25)
Hook leaders we use 20lb fluro.
Hooks is snelled onto the leader and to get the length right for the hook holder use a  palomar knot.. measure off on the boat after the hook is attached, press a fold in the leader at the correct length and use that fold for the bite length when tying the loop in the knot.

Have another sinker at the other end and another buoy

Can lay out from the boat, connect buoy.. sinker.. then hooks.. let tide wind whatever keep the line tight.. last sinker buoy
Or from rear of boat... tie a rag to drag away in current from boat....hooks... then sinker.. attach to rear of the boat
Or similar from shore.
Couple pics of our compact setup for the boat....note .. it doesnt seem to make any difference if have flasher or non flasher hooks....or as u will see in the pic have beads, or floats.