Heathrow Express.
 

Looking for affordable (under $200 for a double)accomodations with access to the Heathrow Express. We are wanting to drop off the rental car and use public transportation for the last two days of our visit in London.

After getting depressed looking at the reviews of the numerous Paddington area hotels (overpriced, crowded, touristy), I opted for staying within cabbing distance instead (said distance will depend on your budget).

In other words, I'd recommend finding an affordable hotel in a neighborhood you want to be in, rather than something within walking distance to Paddington. Several are close enough to be within a 10 pound ride (Bloomsbury, Mayfair, Kensington).

Also, you might check out biddingfortravel to see what kind of Priceline rates people are getting in areas you're interested in staying. I opted for Priceline a couple of years ago and ended up staying at the Millenium Mayfair for less than one of the 3* Paddington hotels would have cost.

Assuming there are at least two of you (you mention "we") I'd not worry about the Heathrow Express. You can get a decent car service for nearly the same amount of money to take you to Heathrow from any other point, rather than struggling to be a block or so to tote your luggage to Paddington.

agree w/ all the above. I'd personally not stay in a hotel simply because it was close to the HEX. You can stay anywhere - if you really want to take the HEX, public transport can get you to nicer areas than right around Paddington. Plus, as NeoPatrick says, a car service will cost about the same as the HEX for 2 people.

I'd pick an area that is convenient for the sights you want to see - Paddington is a bit out on a limb for most London tourism