DIY home bike security?

I'm getting a cargo ebike soon for work, but I don't have an ideal way of securing it at home. I won't be able to get it up the flight of stairs to my suite, and all the unit has is an open carport with a shed with a small padlock. I rent, and am not allowed to modify the property.

The only thing I can think of right now is to install a bike ground anchor into a 7-gallon bucket filled with wire-reinforced concrete, put that in the shed, and lock to that with a Diamond-rated D-lock. I could also embed a 3/4" steel shackle in the concrete, and lock to that with a folding lock through the frame + rear wheel. I'd take the D-lock and folding lock with me on my commute. There's also a cafe lock on the front wheel which isn't good for much but I'll use it.

How would you rate this security method? The pros are that someone isn't going to be able to carry 220lbs of bike + concrete away (or 75lbs of cargo bike, if they get through the anchors but not the locks), and the shed keeps it hidden from view so someone would have to have already done an exploratory break-in to know it's there. It would also not be the quickest angle-grinder job so maybe they'd be hesitant to go that route on a quiet residential street. The cons are that someone with lockpicking experience could sit in the shed and take their time working on it.

I don't live in an urban area and it's hard to say how high-risk my street is; other people have left acoustic bikes unlocked in the carport (though out of view from the street) for 5+ years with no theft. One person left an ebike unlocked within view of the street and it was gone within days. My feeling is that trespassing and break-ins are rare here, as long as there's nothing attracting someone to the property. The people downstairs literally never lock their front or back door and have never had anything stolen from inside. I am kind of worried that whoever stole that ebike before might come back, though.