Anyone do this recently? I'm looking at a ~65 foot run that will need to be trenched, then ran under a sidewalk. Haven't gotten any quotes yet. Thinking maybe I should rent a trencher, lay the conduit and then let a licensed elec. hook everything up as far as the subpanel in the garage.

Depending where your at you will probably need permits. Get them otherwise if you burn something down due to the wiring your hosed.
If you know electricity and panels/subpanels you can you it otherwise hire a electrician.

My rule of thumb on electrical is run everything yourself and then call an actual licensed guy to look it over.

I've done my shop (208vac, 3ph, cnc machines) twice now. I actually enjoy bending conduit and running wire but I still have a guy who does it everyday look it over before turning the power on.

That's about where I am, I know most electricians probably won't want to hassle with trenching in the conduit, so I figure I'd save at least half doing it that way.

I did mine last fall, 85 feet from panel to panel
rented a trencher from K&K true value hardware for $125
dug trench and direct buried cable I got off marketplace 100 feet for $150
put a 50 amp breaker in house and wired up a panel in the garage

all in just over $325 and now I can weld and run my air compressor

I had one 20 amp circuit before

You may not need conduit for the whole length if you use direct burial wire. Depends on the size of the circuit and how deep you want to dig.

I did mine. 26 feet.

I had the trench at 18” deep, nice and squared off in about an hour. No trencher needed.

Had to do the same thing for gas pipe, but at 24”.

I ran conduit in case I decide to upgrade wire size some day. It’s good for 125 amps though.

I ran electric to my workshop when I built it.   Here's what I learned during the process:

Trenching:  Hire someone with a track-hoe or similar to do the trenching.  It's SO MUCH FASTER than renting a trencher yourself.  The guy showed up, I told him I needed minimum 24" (roughly the same run as yours).  He hooked up a 1' wide bucket, and in 10 or fifteen minutes, had the entire trench dug... to 30+".  He also laid the dirt on the edge of the trench very nicely.  I hurried and glued and dropped the conduit in the trench, and in another 5 minutes he'd knocked the dirt back in the trench and packed it down a bit.  If your conduit is close to ready, you can have the entire affair done in less than 30 minutes.  I think it cost me an extra $75 or so above renting a trencher myself, but I didn't have to drive to get the trencher, run the trencher, drive the trencher back, etc..

Conduit:  Run bigger conduit than you think you need.  Conduit is cheap.  Also, while you're at it, throw a second conduit in the trench (this can be smaller) in case you ever want to pull network cable out to the garage for wifi.  Don't screw around with direct burial, the slightest nick in the insulation, and it's GOING to fail later.  Like I said, conduit is cheap.  And if you ever need to pull new cable... conduit makes it a snap.  Really, you're only talking another $30 and 10 minutes to use conduit.

Cable/sizing:  Run a size or two bigger than you plan on, there's always more to power.

Grounding:  You'll need a ground wire run in the conduit, AND a ground rod in the garage.

Pulling the cable:  Use pull boxes to keep the cumulative bends between them reasonable, use lube, and it'll pull easy - especially if you've oversized the conduit.

Inspector:  Every inspector is different, but in my experience, if you've taken your time in your cabling to cross your Ts, dot your Is, and to DO A NEAT AND TIDY JOB, they'll pick up on it right away, and be a lot less likely to give you trouble.  On my inspection, the guy gave a good look in one box, noticed how neat and tidy it all was, then gave a 30-second glance around the room, and said "You're done."

Heating:  If you don't have other heating arrangements, you can easily throw 240V com-pak heaters in between the studs of the garage.

Final thought:  I put exterior lighting all the way around the exterior of my workshop, and they're controlled with 3-way switches, one in the workshop, one inside the house.  If you want to do that (and I do recommend it), run the extra THHN in the conduit for it while you're pulling the main cable.

Sub panels are pretty dang easy.  The most important part is proper wire selection based on amperage and length, and grounding choices.  4 conductors - two ungrounded (hots), one grounded (neutral), one grounding (ground).  The sub-panel ground and neutral are not bonded inside the sub-panel.

In a detached structure (I am not sure if code requires it now) but installing a local ground to earth and bonding to the panel is recommended.

We built our retirement place in 2009 and moved in in 2010. NO PERMITS FOR ANYTHING. It was marvelous compared to the nightmares of living in a "permit" area near a city. I did have to get the aerobic septic system done by a certified installer but no permit or inspection required. Home is 8000 ft. under roof and it's been a winner in all ways. I came out of the housing industry and made trip after trip after trip in the plane to check on things as it was being built. 45 minute flight one way so it was pretty easy.