I have 2 broken items on my 2010

You can get the bulb for few dollars anywhere, an example on ebay now is less than $6. Search for: prius 2010 low beam bulb

As for the door actuator, you could watch ebay. Right now I don't see one for the left side of a 2010 but that changes day by day. For example 2010 2011 10 11 Toyota Prius Right Rear RR RH Door Latch Lock Actuator | eBay is on now. The trick will be installing it.

Set an ebay saved search with daily emails for: prius left door actuator

 

You can buy a headlight (H11 bulb) in any auto supply store/Walmart etc. The left headlight can be replaced without tools - the right side requires you to remove some parts so you can get access.

 

I recently replaced my driver's side low beam headlight. It was easy. I bought a basic bulb, which seems to give the same brightness as before, even if it doesn't last as long: I think it cost $14.nn from a local parts store and I'm sure you can get much cheaper online.

As noted above the passenger side says to unbolt the coolant reservoir (if I recall correctly), although I think people have said you can squeeze your hand in and replace the bulb blind. So, if the passenger's side light has gone and you wanted brighter lights anyway you might take the opportunity and get a new pair of bulbs.

As for the door actuator, I wouldn't have it replaced at a dealer. If it isn't part of the hybrid system, you don't need someone with knowledge of the hybrid system. (Even if you do need hybrid maintenence, you might find an independent garage that will: independent garages have access to all the stuff that dealers do, they're just less likely to have experience).

Quick search on the actuator motor came up with:
2010 TOYOTA PRIUS Front Left Door Lock Actuator Motor

 

Considering the price of the actuator, $500 does not seem unreasonable for the dealer to do it..

 

BOTH left side door actuators started failing on my 2.5 yr-old 2010 w/ 42,000 miles on it. Diagnosis cost me $60 at the dealer, estimate for replacing 2 actuators was over $1030 (out of warranty due to miles). I asked dealer to ask Toyota corporate what they could do. Toyota paid for the actuators, dealer's labor was reduced to $140. A lot better than $2000, but when the coin battery in the fob lasts longer than than the door actuators, something's wrong.

The CD player also just started having problems, but I posted a separate thread about that.

 

Well it is POSSIBLE to replace the passenger side as well without any tools see the other thread !!1

I just did it yesterday ... not as easy as the driver side. The main trick is NOT re-attach the wire as the manual suggest then you will have enough room. I suggest to try with the old bulb a few times. You can not see an do it at the same time. I practiced to put it back like 3 times before trying with the new one .. You do not want dirt on it. And then it is pretty easy to reattach the wiring ...

Also it worth to replace the bulbs in pairs (pair of bulbs sometime cheaper then two individual ones) the halogen lamps are fading overtime so you could distinctly different light output from the two sides.

 

On the doors, you can go to a auto alarm installer, I'm sure they can add a solonoid for ya. Thats usually all that is wrong.

 

Did the dealer actually diagnose the problem as the actuator and eliminate wiring issues, etc.?