If budget is a limitation, I would go for something like this, well known international brand. Else there is a good chance of getting dust flees under you skin and that sort of pleasure.
Ibis is ok located near heathrow. There is a free bus shuttle service from bus station of terminal 1,2,3. Other wise take a paid bus H51 (4.5 pounds)
Food is quite cheap, with corresponding quality.
There is a bowling alley (also inexpensive) that has a Spanish food corner in it. Also the bowling alley offers parking for half the price Ibis is charging. Might be worth a try for a long term rentals.
Rooms are tiny. Bathrooms are cleanish. Carpeting is old. Beds are okish