Had my 7.5 for near 4 years and never had a trailor. If its used (as yours is ) and lifted out ( as yours is) they do seem a little pointless , but the crunch comes if you do need to take it somewhere - for whatever reason and then you need one . My boat was lifted out each winter in a yard so no need for one even if you dont use the boat all year round.
When I needed it out ( to fix the tube ) of the water I 'borrowed' a versa dock berth in the marina so no issue there as I am sure you could do the same - but then its lifted easilty for work etc anyway.
You can try to beg , borrow or hire one which ( in my experience ) never quite fits right..... and then buying another can get expensive as no -one wants to buy a new one so a decent used one holds its value I think.
If your neighbours dont like it now wait until you stick the boat on it and park it in the drive...
but a lot of houses have covenents that technically mean your not allowed to 'store' boats & caravans etc .....